Extraction cleaner

ABSTRACT

A cleaning device having a housing, a hose assembly and a cleaning head. The housing has a first supply tank to contain a first fluid, a recovery tank, a vacuum fan to generate a working air flow through the recovery tank, and a fluid pump having an inlet and an outlet. The pump inlet receives the first fluid from the first supply tank. The hose assembly has a proximal end connected to the housing and a distal end freely moveable relative to the housing, and includes a vacuum hose in communication with the recovery tank and a fluid hose in communication with the pump outlet. The cleaning head is connected to the distal end of the hose assembly, and has an inlet nozzle and a fluid deposition system. The fluid deposition system has a second supply tank to contain a second fluid, a fluid mixer to mix the first fluid with the second fluid, and a first fluid sprayer downstream from the fluid mixer. The second supply tank is selectively removable from the cleaning head and has a dry-break valve that automatically seals the second supply tank upon its removal from the cleaning head.

FIELD OF THE INVENTION

The present invention relates to extraction cleaning devices for floor, upholstery and fabric care.

BACKGROUND OF THE INVENTION

Many types of cleaning devices are available for commercial and consumer cleaning needs. While conventional vacuums are popular for general floor cleaning, various types of extraction cleaners have been developed to provide deeper or more problem-specific cleaning operations. Extraction cleaners generally use a liquid or dry composition depositing system in conjunction with a vacuum source to deposit a cleaning substance on the surface being treated, then recover the deposited cleaning substance and any entrained dirt or debris back into the extractor. Extractors can also be used or adapted to deposit other types of compound on the surface, such as sealers and protectants. Like vacuums, extractors are provided in many different forms, such as upright, portable, canister, and handheld.

Typical wet extractors use a fluid dispensing system having a fluid reservoir to store a detergent mixture, a pump to pressurize the mixture, and a fluid conduit to convey the pressurized fluid mixture to the surface to be cleaned. Many variations on this design have been produced. For example, some wet extractors store concentrated detergent and water in two separate reservoirs, and mix the two at some point in the process of conveying it to the surface to be cleaned. It is also known in upright extractors to supply the cleaning fluid by gravity. U.S. Pat. Nos. 6,082,376, 4,458,377, 6,125,498, 6,378,162, 4,809,396, 6,167,586, and 5,615,448, which are incorporated by reference herein, show these and various other wet extractor configurations and features.

The cleaning fluid, along with any entrained dirt or debris, is recovered by applying a vacuum to the surface. The vacuum is generated by a vacuum pump, such as a conventional fan and motor assembly, that creates a working airflow within the extractor that extends from the inlet nozzle (typically a narrow slit) to a recovery tank. The recovery tank is usually positioned, in a fluid sense, between the inlet nozzle and the vacuum source to prevent fluid and dirt from contaminating the vacuum fan or motor, but it is also known to locate the recovery tank fluidly downstream of the vacuum source. Typical recovery tanks comprise a removable chamber having a float and valve arrangement that closes the path to the vacuum source when the tank reaches a predetermined fill level to prevent fluid from entering the suction source.

Wet extractors are often operated in a two-step process. In the first step, the cleaning step, the cleaning fluid is deposited on the surface being cleaned, then recovered along with any entrained dirt and debris. In the second step, the rinsing step, the cleaning fluid is replaced with clean water, which is deposited on and recovered from the surface to rinse away any remnants of the cleaning fluid. While known extractors have proved useful for cleaning carpets, upholstery and other fabrics and textiles, this second rinsing step has been found to be inconvenient and time consuming because remnants of the cleaning fluid often remain in the fluid conduit between the fluid reservoir (or reservoirs) and the conduit outlet. As such, operators typically must flush the fluid that remains in the fluid conduit before beginning the clean water rinse cycle, and may also need to remove the pre-mixed cleaning solution from the reservoir and replace it with clean water for rinsing. Such flushing may be inconvenient, and may waste cleaning solution. Similar problems may arise when using dry chemical extraction devices.

In view of these and other problems with the known extraction cleaning devices, there remains a need to provide an improved extraction cleaning device.

SUMMARY OF THE INVENTION

In one aspect, the present invention provides a cleaning device having a housing, a hose assembly and a cleaning head. The housing is adapted to hold a first supply tank adapted to contain a first fluid, a recovery tank, a vacuum fan adapted to generate a working air flow through the recovery tank, and a fluid pump having a pump inlet and a pump outlet. The pump inlet is adapted to receive the first fluid from the first supply tank. The hose assembly has a proximal end connected to the housing and a distal end freely moveable relative to the housing, and includes a vacuum hose in communication with the recovery tank and a fluid hose in communication with the pump outlet. The cleaning head is connected to the distal end of the hose assembly, and has an inlet nozzle in communication with the vacuum hose and a fluid deposition system in communication with the fluid hose. The fluid deposition system has a second supply tank adapted to contain a second fluid, a fluid mixer adapted to mix the first fluid with the second fluid, and a first fluid sprayer located downstream from the fluid mixer. The second supply tank is selectively removable from the cleaning head and has a dry-break valve that automatically seals the second supply tank upon removal of the second supply tank from the cleaning head.

In another aspect, the present invention provides a cleaning device having a housing, a hose assembly and a cleaning head. The housing is adapted to hold a first supply tank adapted to contain a first fluid, a recovery tank, a vacuum fan adapted to generate a working air flow through the recovery tank, and a fluid pump having a pump inlet and a pump outlet. The pump inlet is adapted to receive the first fluid from the first supply tank. The hose assembly has a proximal end connected to the housing and a distal end freely moveable relative to the housing, and includes a vacuum hose in communication with the recovery tank and a fluid hose in communication with the pump outlet. The cleaning head is connected to the distal end of the hose assembly, and has an inlet nozzle in communication with the vacuum hose and a fluid deposition system in communication with the fluid hose. The fluid deposition system has a second supply tank adapted to contain a second fluid, a tank receptacle, a fluid mixer adapted to mix the first fluid with the second fluid, and a first fluid sprayer, located downstream from the fluid mixer. The second supply tank is selectively removable from the cleaning head, and the tank receptacle is adapted to receive substantially the entire second supply tank. The tank receptacle has an open portion through which at least a portion of the second supply tank is visible.

In still another aspect, the present invention provides a cleaning device having a housing, a hose assembly and a cleaning head. The housing is adapted to hold a first supply tank adapted to contain a first fluid, a recovery tank, a vacuum fan adapted to generate a working air flow through the recovery tank, and a fluid pump having a pump inlet and a pump outlet. The pump inlet is adapted to receive the first fluid from the first supply tank. The hose assembly has a proximal end connected to the housing and a distal end that is freely moveable relative to the housing, and includes a vacuum hose in communication with the recovery tank, a fluid hose in communication with the pump outlet, and a hose cuff located at the distal end. The cleaning head has an inlet nozzle in communication with the vacuum hose and a fluid deposition system in communication with the fluid hose. The fluid deposition system includes a flow valve adapted to block the flow of the first fluid in an off position, and allow the flow of the first fluid in at least one operating position, a second supply tank adapted to contain a second fluid, a fluid mixer adapted to mix the first fluid with the second fluid, and a first fluid sprayer, located downstream from the fluid mixer. The cleaning head is selectively connectable to the hose cuff such that the cleaning head can be simultaneously connected to the vacuum hose and the fluid hose.

In still another aspect, the invention provides a cleaning device having a housing, a hose assembly and a cleaning head comprising. The housing is adapted to hold a first supply tank adapted to contain a first fluid, a recovery tank, a vacuum fan adapted to generate a working air flow through the recovery tank, and a fluid pump having a pump inlet and a pump outlet. The pump inlet is adapted to receive the first fluid from the first supply tank. The hose assembly has a proximal end connected to the housing and a distal end freely moveable relative to the housing, and includes a vacuum hose in communication with the recovery tank and a fluid hose in communication with the pump outlet. The cleaning head is connected to the distal end of the hose assembly, and has an inlet nozzle in communication with the vacuum hose, a handle, and a fluid deposition system in communication with the fluid hose. The fluid deposition system includes a flow valve adapted to block the flow of the first fluid in an off position, and allow the flow of the first fluid in at least one operating position, a second supply tank adapted to contain a second fluid, a fluid mixer adapted to mix the first fluid with the second fluid, a first fluid sprayer, located downstream from the fluid mixer, and a diverter valve adapted to create a rinse flow path from the fluid hose to a second fluid sprayer, such that the rinse flow path bypasses the fluid mixer. The flow valve and the diverter valve are positioned proximal to the handle such that a user can grip the handle in one hand and operate the flow valve and the diverter valve with the one hand without releasing the handle.

In still another aspect, the present invention provides a cleaning device having a housing, a hose assembly and a cleaning head. The housing is adapted to hold a first supply tank adapted to contain a first fluid, a recovery tank, a vacuum fan adapted to generate a working air flow through the recovery tank, and a fluid pump having a pump inlet and a pump outlet. The pump inlet is adapted to receive the first fluid from the first supply tank. The hose assembly has a proximal end connected to the housing and a distal end freely moveable relative to the housing, and includes a vacuum hose in communication with the recovery tank and a fluid hose in communication with the pump outlet. The cleaning head is connected to the distal end of the hose assembly, and has an inlet nozzle in communication with the vacuum hose and a fluid deposition system in communication with the fluid hose. The fluid deposition system has a second supply tank adapted to contain a second fluid, a third supply tank connected to the second supply tank and adapted to contain a third fluid, a fluid mixer adapted to selectively mix the first fluid with the second fluid in a first mixer position, and with the third fluid in a second mixer position, and a first fluid sprayer located downstream from the fluid mixer.

In yet another aspect, the present invention provides a cleaning device having a first supply tank adapted to contain a first fluid, a recovery tank, a vacuum fan adapted to generate a working air flow through the recovery tank, a fluid pump having a pump inlet and a pump outlet, a fluid supply hose connected to the pump outlet, and a bypass valve fluidly positioned between the pump inlet and the fluid supply hose. The pump inlet is adapted to receive the first fluid from the first supply tank. The cleaning device also has a fluid deposition system in communication with the fluid supply hose. The fluid deposition system has a flow valve adapted to block the flow of the first fluid in an off position, and allow the flow of the first fluid in at least one operating position, and a first fluid sprayer located downstream from the flow valve. The bypass valve is adapted to open when the flow valve is in the off position.

In still another aspect, the present invention provides a cleaning device having a housing with an air inlet, an air outlet and a motor cooling path therebetween. A first supply tank is selectively removable from the housing and is adapted to contain a first fluid. A recovery tank is also provided and is selectively removable from the housing. A vacuum fan is located within the housing, and a fan motor is located within the motor cooling path and adapted to drive the vacuum fan to generate a working air flow through the recovery tank. A motor cooling fan is located within the motor cooling path and adapted to generate a cooling air flow along the motor cooling path that enters the housing through the air inlet, is heated by the fan motor, and exits the housing through the air outlet. The device also includes a fluid deposition system that is fluidly connected to the first supply tank, and adapted to deposit the first fluid on a surface to be cleaned. The first supply tank is located adjacent at least a portion of the motor cooling path between the fan motor and the air outlet, and the first fluid is adapted to be heated by the cooling air flow.

In another aspect, the present invention provides a cleaning device having a housing, a supply tank selectively removable from the housing and adapted to contain a fluid, a recovery tank, a vacuum fan adapted to generate a working air flow through the recovery tank, and a temperature sensor. The temperature sensor has a first element attached to the supply tank, a second element attached to the housing, and a display positioned to indicate the thermal condition of the fluid to an operator.

In still another aspect, the present invention provides a cleaning device having a housing, a supply tank selectively removable from the housing and adapted to contain a fluid, a recovery tank, a vacuum fan adapted to generate a working air flow through the recovery tank, and a temperature sensor attached to the supply tank and adapted to indicate the thermal condition of the fluid to an operator.

In yet another aspect, the present invention provides a cleaning device having a fluid supply system, a fluid recovery system, and one or more ultraviolet lights adapted to irradiate the fluid supply system and/or the fluid recovery system. The fluid supply system has a first supply tank for containing a fluid, and a fluid deposition system, associated with the first supply tank and adapted to deposit the fluid on a surface to be cleaned. The fluid recovery system has a recovery tank, an inlet nozzle, and a vacuum fan adapted to generate a working air flow from the inlet nozzle to the recovery tank.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front isometric view of an embodiment of an extractor of the present invention.

FIG. 2 is a rear isometric view of the extractor of FIG. 1.

FIG. 3 is an exploded isometric view of the extractor base assembly of FIG. 1.

FIG. 4 is an exploded view of the main supply tank of FIG. 1.

FIGS. 5A and 5B are cross sectional views of the dry-break valve of FIG. 4, shown in closed and opened positions, respectively.

FIG. 6 is an exploded view of the recovery tank assembly of FIG. 1.

FIG. 7 is a partially cutaway exploded view of the base assembly and recovery tank of FIG. 1.

FIG. 8 is a schematic drawing showing the working air flow path of the extractor of FIG. 1.

FIG. 9 is an isometric view of the cleaning head assembly and hose connector of FIG. 1.

FIG. 10 is an exploded view of the cleaning head assembly and hose connector of FIG. 9.

FIG. 11 is a schematic diagram of the fluid system of the cleaning head assembly of FIGS. 9 and 10.

FIG. 12 is an exploded view of the handle assembly of FIG. 1.

FIG. 13 is a cross-sectional view of the handle pivot of FIG. 12.

FIG. 14 is a sectional view of the handle pivot of FIG. 12 as seen along line 14-14, of FIG. 13, shown in conjunction with various other parts.

FIG. 15 is a schematic diagram of another embodiment of a fluid system of the present invention.

FIG. 16 is a schematic diagram of an embodiment of a fluid pumping system of the present invention.

FIG. 17 is an exploded view of an alternative embodiment of a handle assembly of the present invention.

FIG. 18 is a fragmented, cross-sectional view of the pivot assembly of the embodiment of FIG. 17.

FIG. 19 is a schematic drawing showing an alternative working air flow path of a wet extractor of an embodiment of the present invention incorporating the handle assembly of FIG. 17.

FIG. 20 is a schematic drawing of a fluid heating system of another embodiment of the present invention.

FIG. 21 is a schematic drawing of another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides an improved wet extraction cleaning machine having a unique and useful housing construction and layout for providing improved compactness and efficiency. The present invention also provides a unique fluid system providing enhanced control over the mixture of detergent and water, and quick changing between depositing a detergent/water mixture and pure water, which allows for quicker and more efficient rinsing operations. The present invention also provides the ability to quickly change between various cleaning solutions, improved on-board tool and hose storage capability, and various other features as will be appreciated by those of ordinary skill in the art.

Referring now to FIGS. 1 and 2, in a preferred embodiment, the present invention provides a portable wet extractor 100 having a base assembly 102 and a carry handle 104 attached thereto. The carry handle 104 preferably is pivotally attached, as described later herein, but may instead be rigidly attached. In embodiments in which the inventions described herein are used in conjunction with upright devices, the base assembly 102 may be replaced by a housing having a base portion and an upright handle portion, and the carry handle 104 may be omitted.

The extractor 100 includes a removable fluid supply tank 106 and a removable recovery tank 108, which preferably are retained in the upper surface of the base assembly 102 in a laterally juxtaposed orientation. That is, the supply and recovery tanks 106, 108 are on opposite sides of the long axis of the device. The supply and recovery tanks 106, 108 may be individually removable, or may be connected to one another to allow removal together. A cleaning head 110 is provided, and is preferably configured such that it nests in a pocket 111 in the base assembly 102, and in a channel 113 created between the supply and recovery tanks 106, 108. A vacuum hose 112 is provided to connect the cleaning head 110 to a vacuum fan 324 (FIG. 3), by way of the recovery tank 108, and a liquid supply hose (not visible) is contained within the vacuum hose 112 to connect the cleaning head 110 to the supply tank 106 by way of a fluid pump 312 (FIG. 3). The vacuum hose 112 and liquid supply hose may be attached or joined with one another, either continuously along their lengths or only at various points, to form a hose assembly. One way of doing this is to simply locate the liquid supply hose within the vacuum hose 112 (as shown), but it may also be accomplished by mounting the liquid supply hose to the exterior of the vacuum hose 112 by any suitable method, such as by using removable or permanent clips.

Preferably, the vacuum hose 112 is fixedly attached to the base housing 102 or to a part or parts therein or thereon (i.e., attached such that it is not intended to be detached during general use, but may be detached and reattached when cleaning the device or for other service). It is also preferred for the vacuum hose 112 to be selectively attachable to the cleaning head 110 (i.e., attached such that it is readily connected or disconnected during general use). While the preceding attachments are preferred, they may altered, reversed, or otherwise varied, as will be appreciated by those of ordinary skill in the art in light of the teachings herein. The base assembly 102 and various working parts of the wet extractor 100 are shown in more detail in FIG. 3. In this figure, the base assembly 102 is shown as comprising an upper housing 302 and a lower housing 304 that cooperate together to form an enclosed chamber housing various parts of the extractor 100. The lower housing 304 has a generally flat lower surface 306, which may comprise feet, wheels or casters projecting from the bottom thereof. The lower housing 304 also has a collecting trough 305, which is a walled-in portion surrounding a hole (not visible) through the lower surface 306 of the lower housing 304. As described later herein with reference to FIG. 16, the collecting trough 305 and its associated hole are located below a fluid system vent hose (not shown), and are used to collect fluid that may seep out of the fluid system, and allow such leaking fluid to exit the lower housing 304 without collecting elsewhere on its lower surface 306.

A number of fastener bosses 308 are provided for passing fasteners (preferably screws) therethrough to secure the upper and lower housings 302, 304 together. The lower housing 304 also includes a fluid pump mount 310, into which the bottom of a fluid pump 312 fits. The pump mount 310 has, in this preferred embodiment, the form of two ribs that form a cradle, but may be otherwise shaped. An additional rib (not shown) is also provided below the fluid pump 312 to provided additional support thereto, and other support structures may be used instead. The pump 310 is secured in the base housing 102 by an upper pump mount 314 that is shaped to fit over and capture the pump 312 in place. The upper mount 314 may be attached to the lower housing 304 by its fasteners, may be captured in place between the upper and lower housings 302, 304, or may be attached to the upper housing 302 in the appropriate location to capture the pump 312 when the upper housing 302 is attached to the lower housing 304. Vibration- or noise-reducing padding may be placed between the pump 312 and the mounts 310, 314 if desired.

The pump 312 is provided for pressurizing fluid from the supply tank 106 and conveying it to the cleaning head 110. Any type of pump can be used, such as an electric motor 316 adapted to drive a centrifugal pump 318, a vacuum-driven pump, self-priming pumps, and so on. When an electric motor-driven pump is used, a cooling fan 320 may optionally be provided on the motor 316 to cool it, as shown. The inlet of the pump 312 is connected to the supply tank 106 by way of a fluid hose (not shown) that leads to a dry-break receptacle 370 (shown in more detail in FIGS. 5A-B). A check valve (not shown) may also be provided to prevent backflow from the pump to the dry-break fitting. The pump's outlet is connected to the cleaning head 110 by way of another fluid hose 902 (FIG. 12). A heater or heating elements, or an arrangement that depends on heat transfer from electric motors within the device to the water supply by thermal conduction may also be provided to heat the fluid, as will be appreciated by those of ordinary skill in the art.

A vacuum fan assembly 322 is also contained in the base housing 102. The vacuum fan assembly 322 comprises a vacuum fan 324 that is driven by an electric fan motor 326. The vacuum fan 324 may be any type of impeller or fan arrangement that generates a working air flow in the device when the electric motor 326 is activated. The vacuum fan 324 and fan motor 326 are contained between first and second housing shells 328, 330. One or both of the fan motor 326 and the vacuum fan 324 may be mounted within the first and second housing shells 328, 330 on vibration- or noise-reducing isolation mounts, and the assembly may include various seals and gaskets to help control or isolate the airflow within it, as will be appreciated by those of ordinary skill in the art.

The first housing shell 328 encases the vacuum fan 324 and includes an inlet passage 332 that directs air to the vacuum fan inlet (not visible), and an outlet passage 334 that conveys air exiting the vacuum fan outlets 336. The first housing shell 328 may be partially formed by an additional cover 338. Such a cover 338 is not required, but may be useful to reduce production costs or complexity, especially when it is desired to form the first housing shell 328 as a complex part that defies conventional or practical forming operations. Of course, these well-understood principles of part manufacture and cost control are equally applicable for the other parts of the invention, particularly parts that are conveniently made as molded plastic parts (such as the upper and lower housings 302, 304), which may be formed either as monolithic pieces that are formed in a single operation, or as conglomerations of separately-manufactured pieces that are assembled together to form the final part.

The second housing shell 330 encases the fan motor 326 and includes an inlet 340 into which air is drawn by a motor cooling fan 342, and an outlet (not visible) located near the other end of the fan motor 326. In operation, the motor cooling fan 342 produces a cooling air flow that passes over and cools the fan motor 326. While the second housing shell 330 is not required, it is useful to improve motor cooling and to prevent unregulated release of heated air from the motor into the base housing 102. Air is provided to the interior of the base housing assembly 102 through one or more housing inlet vents 341. The housing inlet vents 341 are preferably located above the lower surface 306 of the lower housing 304, so that any suction created by the motor cooling fan 342 does not draw fluid or objects into the housing inlet vents 341.

The installation of vacuum fan assembly 322 may be executed in a similar manner as the pump mounting. In a preferred embodiment, the lower housing 304 is provided with a pair of ribs that form a vacuum fan assembly mount 344. A corresponding surface or surfaces in the upper housing 302 capture the vacuum fan assembly 322 in place when the housings are assembled together. In addition, fasteners are used to secure the vacuum fan assembly 322 to the upper housing 302. Vibration- or noise-reducing materials may be provided between the vacuum fan assembly 322 and its mounts. Of course, other vacuum fan assembly mounting arrangements may be used. For example, the vacuum fan assembly mount 344 may simply comprise one or more fasteners (such as screws) that pass through the lower housing 304 to hold the vacuum fan assembly 322 in place, or the device may be provided with straps that retain the vacuum fan assembly 322. Other variations will be apparent to those of ordinary skill in the art.

An exhaust assembly 346 may also be provided in the base housing 102. The exhaust assembly 346 is provided to direct air exiting the vacuum fan 324 and the fan motor 326 to a vent 350. The vent 350 may be located in either the upper or lower housing 302, 304, and may be directed downward to reduce the noise level of the device. As shown in FIG. 3, the exhaust assembly 346 comprises a separate insert that cooperates with the lower housing 304 to form an enclosed air passage or air passages between the housing shells 328, 330 of the vacuum fan assembly 322 and the vent 350. In the shown embodiment, the exhaust assembly is formed from first and second halves 348, 352 that are fastened, snapped, or bonded together. When installed, a first inlet 354 into the exhaust assembly 346 is aligned to receive working air from the vacuum fan 324 that exits the first housing shell outlet 334. A second inlet 356 receives motor cooling air from the previously mentioned motor exhaust opening through the second housing shell 330. The two airflows may combine in the exhaust assembly 326, but are preferably kept separate from one another by a wall (not shown) within the exhaust assembly 346. The exhaust assembly 346 is attached to or pressed against the lower housing 304 at the vent 350, and sealed by a sealing gasket, weld, or other air- and fluid-impervious seal (not shown) to prevent pressurized air exiting the vacuum fan assembly 322 from recirculating into the base assembly 102. This seal also prevents any fluid that may pass through the vacuum fan 324 from entering the base assembly 102, thereby reducing the risk of presenting an shock hazard. The use of this exhaust assembly 346 separates the working air exiting the device from the cooling air that passes over the motor 326 (this arrangement is referred to as a by-pass motor arrangement). The exhaust assembly 346 may also be shaped or provided with features (such as vanes, baffles, foam inserts, filters and the like) to reduce particulate emissions, reduce the noise level of the device, or provide other benefits.

The base assembly of FIG. 3 also includes an inlet air conduit 358, which, like other complexly-shaped parts described herein may be formed, in part, by an additional closing wall 360. The inlet air conduit 358 is shaped and positioned to receive vacuumed air and fluid from the cleaning head 110 (FIG. 1) and direct it to the recovery tank 108 (FIG. 1). As with the other parts described herein, the inlet air conduit 358 may be captured or bonded in place, retained by fasteners or otherwise held between the upper and lower housings 302, 304. The inlet air conduit 358 comprises an inlet opening 362 and an outlet opening 364 that are connected by an enclosed passage. The inlet opening 364 is positioned such that it receives working air from a hollow handle pivot 386, and the outlet opening 364 is positioned to mate with a working air inlet 610 (FIG. 6) into the recovery tank 108. The location and operation of this part is described in more detail herein with reference to FIGS. 6 through 8.

Still referring to FIG. 3, the upper housing 302 fits on top of the lower housing 304, and the two housings abut one another along their respective edges to form an enclosure. Fasteners (not shown) are preferably used to hold the upper and lower housings 302, 304 together, but they may instead be held by clamps, bonding, or other means. When assembled, the upper and lower housings 302, 304 safely enclose the various working parts of the device to which the user does not need regular access.

The upper housing 302 has a first pocket 366 that is adapted to receive the supply tank 106 (FIG. 1), and a second pocket 368 adapted to receive the recovery tank 108 (FIG. 1). As explained in more detail with reference to FIG. 20, the first pocket 366 may optionally be adapted to help transfer heat from the fan motor 326 to the fluid in the supply tank 106. To do so, the first pocket 366 may be provided with an air passage to receive hot air passing over the fan motor 326, however this might result in an unacceptable shock hazard. More preferably, the first pocket 366 is provided with one or more heat transfer enhancing surfaces, such as relatively highly thermally conductive surfaces 367 like metal plates. The conductive surfaces 367 may simply be attached to the wall of the first pocket 366. For example, a foil could be adhered to the wall or the wall can be treated with a thermally conductive coating. More preferably, a portion of the pocket wall is formed by a conductive surface 367, or the plastic or other material forming the pocket wall is impregnated with thermally conductive material, such as metal particles or strands, during the molding process to form the surface 367. The use of multiple shot molding processes can facilitate molding the conductive surface 367 in place in the upper housing 302. While the conductive surface 367 is shown in the lower wall of the first pocket 366, it may instead be located in other walls or in more than one wall.

The first and second pockets 366, 368 and their respective tanks 106, 108 preferably are made such that the tanks 106, 108 can be vertically lowered into the pockets 366, 368, and held in place by gravity or by gravity and snap fittings. Such snap fittings may simply comprise protrusions in the pockets 366, 368 that snap into corresponding detents on the tanks 106, 108, or any other engagement by resiliently biased parts. Of course, other engagement devices may be used to retain the tanks 106, 108 instead, such as a tapered sliding engagement, clamps or other locking devices. The first pocket 366 includes a dry-break receptacle 370, described in detail with reference to FIGS. 5A and 5B, that is adapted to mate with a corresponding fitting 418 (FIG. 4) in the supply tank 106 to provide fluid to the device. Similarly, the second pocket 368 has an opening therethrough (see FIG. 7) that is adapted to allow fluid communication between the recovery tank 108 and the outlet opening 364 of the inlet air conduit 358 and the inlet passage 332 of the first vacuum assembly housing shell 328.

The upper housing 302 preferably is also provided with an opening 372 into which the cleaning head 110 is adapted to fit, as shown in FIG. 1. The supply and recovery tanks 106, 108 may also be shaped to make room for the cleaning head 110. The upper housing 302 (or lower housing 304) also may include one or more pockets that are adapted to hold spare auxiliary supply tanks 932 (see FIGS. 9 and 10), accessory tools, or other useful parts or supplies.

A power switch 374 is provided in a corresponding opening 376 in the upper housing 302. Wiring (not shown) connects the switch 374 to the fan motor 326 and/or pump motor 316 in a known manner. In a preferred embodiment, the switch 374 activates the fan motor 326 and pump motor 316 simultaneously, but the switch 374 may be a three-position switch in which the first position de-energizes the device, the second position energizes just the vacuum motor 326, and the third position energizes both the vacuum motor 326 and the pump motor 316. The vacuum motor 326 and pump motor 316 may also be separately controlled by separate switches. In any of these embodiments, one or more of the switches may be positioned on the cleaning head 110, rather than on the base 102 assembly. The wiring and fluid plumbing for device are excluded from these drawings solely for the sake of clarity of illustration, but these features will be well understood by those of ordinary skill in the art.

The upper housing 302 may also be provided with an electrical cord holding device, such as an upper hook 378 and a lower hook 380. the upper and lower hook 378, 380 face in opposite directions, as shown in FIG. 2, so that an electrical cord (not shown) can be wrapped around them and retained on the device. The lower hook 380 preferably is rotatable so that it can be turned upwards to allow easy removal of the cord without having to unwind it. The device may alternatively have a cord reel mechanism that stores the cord on an internally-contained reel assembly. Such a cord reel may be operated by hand, a spring, a motor, or other of various well-known means to retract the cord. The device may also be powered by one or more batteries.

The upper housing 302 also includes a pair of handle pivot holes 382 (one of which is visible). The handle pivot holes 382 are adapted to receive handle pivot bushings 384, which in turn hold a handle pivot 386. The handle pivot 386 has a hollow portion therein that forms a portion of the working air passage between the cleaning head 110 and the recovery tank 108. A portion of the fluid hose 902 (FIG. 12) between the pump 312 and the cleaning head 110 is also contained within the handle pivot 386, and access into the handle pivot 386 for the fluid hose 902 is provided by a circumferential slot 390, as also shown in FIG. 13. The construction and operation of the handle pivot 386 is described in more detail herein with reference to FIGS. 12 and 13. The upper housing 302 also includes a handle stop 388, the features and operation of which are also described elsewhere herein with reference to FIG. 14.

Turning now to FIGS. 4 through 5B, the supply tank 106 and its related parts are described in greater detail. The supply tank 106, which may be used to provide either fresh water, detergent, or a mixture of water and detergent, is formed from first and second supply tank halves 402, 404 that are bonded along their edges to form a generally fluid-tight seam. It is preferred for one or both of the supply tank halves 402, 404 to be formed from a transparent or partly-transparent plastic material to allow an operator to view the contents of the supply tank 106. However, in an embodiment in which the supply tank 108 is operated in conjunction with a heater or steam generator (not shown), as are known in the art, it is preferred for the walls to be insulated or double-walled to contain the heated fluid. In such a case, metal walls may be more appropriate. The exterior surfaces of the supply tank 106, particularly the lower portions thereof, are shaped to slidably engage with the upper housing 302, and may also be shaped to form one or more integral handles to facilitate its removal and manipulation. Of course, the supply tank 106 may also include separate handles that are attached thereto.

The supply tank 106 comprises a selectively sealable inlet 406 having a cover 408 or a screw-on cap. The cover 408 preferably is made from a flexible material, and may be provided with a pin 410 that is pressed into and captured in a corresponding hole 412 in the supply tank 106 wall, to thereby retain the cover 408 when it is removed from the inlet 406. A vent hole 414 is provided in the cover 408 or in the tank walls near the uppermost extent of the supply tank 106. The cover pin hole 412 may also serve as a vent hole if the tolerance between the hole 412 and the pin 410 is great enough to allow air to pass therethrough. The supply tank 306 has an outlet 416 in its lowermost wall, and a dry-break outlet fitting 418, as are known in the art, is positioned in the outlet 416 to prevent the escape of fluid when the supply tank 106 is not installed in the device. Also shown in FIG. 4 are detents 420 in the supply tank walls into which corresponding protrusions in the upper housing 302 fit to hold the supply tank 106 in place by snap engagement.

The supply tank 106 optionally includes thermally conductive surfaces 422, such as those described with reference to the first pocket 366 shown in FIG. 3. Such conductive surfaces 422 may comprise thermally conductive material that is attached to the surface of the walls that form the supply tank 106, or may be a plate of conductive material that forms the supply tank walls. The thermally conductive surfaces 422 assist with transferring heat from the fan motor 326 to the fluid in the supply tank 106, as described in more detail with reference to FIG. 20. Any construction or material for the thermally conductive surfaces 422 can be used, and they may be located on or form any of the walls of the supply tank 106.

The operation of the dry-break outlet 418 is shown in FIGS. 5A and 5B. As shown, the dry-break outlet 418 is positioned to engage with a corresponding dry-break receptacle 370 in the upper housing 302 (FIG. 3) when the supply tank 106 is placed in the device. The dry-break outlet 418 comprises a boot seal 502 that surrounds a hollow central member 504. The boot seal 502 is configured to frictionally fit within a hole in the lowermost wall of supply tank 106, and has a skirt portion 506 that extends downward to seal with a the corresponding dry-break receptacle 370. A sliding valve member 508 is disposed in the bore of the hollow central member 504, and pre-loaded by a spring 510 that biases the valve member 508 downward. When in this position, a rubber plug 512 abuts the upper end of the hollow central member 504 to seal the exit from supply tank 106. When the dry-break outlet 418 is pushed downward into engagement with the dry-break receptacle 370, as shown in FIG. 5B, a pin 514 provided in the upper housing 302 pushes the sliding member 508 upwards against the spring 510 bias, thereby opening the seal formed by the rubber plug 512 and permitting fluid to flow out of the supply tank 106 and into a fluid inlet 516 at the bottom of the dry-break receptacle 370. The receptacle 370 may also be provided with a fitting 518 to which a hose (not shown) leading to the inlet of the pump 312 may be attached.

The supply tank 106 preferably is shaped so that it has a low profile when it is oriented to be filled. This allows the supply tank 106 to be filled even when relatively little vertical room is available, as is often the case in bathroom sinks, in which the sink basin is typically shallower and the faucet is typically lower than in kitchen or utility sinks. In order to accomplish this goal, the exterior walls of the supply tank 106 define a flattened outer periphery having its inlet 406 located on a flattened side thereof. In this embodiment, the supply tank 106 is filled by removing it from the base assembly 102, removing the cover 408, turning the tank on its side, and positioning the inlet 406 under a faucet. The narrow, flattened profile of the supply tank 106 provides substantially more clearance than typical supply tanks, and allows the inlet 406 to be positioned under faucets in sinks that have relatively shallow basins and low faucets.

An embodiment of a recovery tank 108 of the present invention is shown in exploded view in FIG. 6. In this preferred embodiment, the recovery tank 108, is constructed from first and second recovery tank halves 602, 604 that are attached to one another in any suitable way to form an essentially fluid-tight container. As with the supply tank 106, it is preferred that at least one of the halves 602, 604 be made of a transparent or partially transparent material to allow viewing the contents of the recovery tank 108. The exterior surfaces of the recovery tank 108, particularly the lower portions thereof, are shaped to slidably engage with the upper housing 302, and may also be shaped to form one or more integral handles to facilitate its removal and manipulation. One such integral handle is shown as being formed under a lip 606 near the top of the recovery tank 108. Of course, the recovery tank 108 may also have separate handles attached to it. The recovery tank 108 is also provided with detents 608 into which corresponding protrusions in the upper housing 302 fit to hold the recovery tank 108 in place by snap engagement.

The recovery tank 108 is provided with a working air inlet 610 that, when installed in the device, fits over the outlet 364 of the inlet air conduit 358 in the base assembly 102 to form a continuous fluid conduit to the cleaning head 110. The recovery tank 108 also has a working air outlet 612 that fits over the inlet passage 332 to the vacuum fan assembly 322 to form a continuous path to the vacuum fan 324. it will be appreciated that when the vacuum fan 324 is activated, it applies a vacuum to the working air outlet 612, which is conveyed to the working air inlet 610 and the cleaning head 110 to extract water and entrained soil for the surface being cleaned. The recovery tank 108 also has a drain outlet 614 that is selectively sealed by a drain cover 616 to allow an operator to conveniently drain the contents of the recovery tank 108. The drain cover 616 preferably has a pin 618 that is attached to a corresponding hole (not shown) in the recovery tank 108 to secure the cover to the recovery tank 108 when it is not covering the drain outlet 614. The drain cover 616 may also be identical to the supply tank cover 408 to reduce manufacturing costs.

The recovery tank 108 is provided with an internal assembly 619 that prevents the working air from going directly from the working air inlet 610 to the working air outlet 612 without first depositing any liquid and entrained soil into the recovery tank 108. The internal assembly 619 includes an air router 620, a diverter 622, a float assembly having a float 624 and a float linkage 626, and a door 628.

The air router 620 has two passages through it. The first passage is a dirty air passage 802 (FIG. 8) having an inlet 630 on the bottom of the air router 620, and an outlet 632 on the front face of the air router 620. The dirty air passage 802 conveys liquid- and soil-laden air from the working air inlet 610 and passes it into the diverter 622, which has a downwardly-angled exit 634 to direct the incoming dirty air down to the lower portion of the recovery tank 108. The second passage through the air router 620 is a clean air passage 804 (FIG. 8), which has an inlet 636 on the front face of the air router 620 and an outlet 638 on the bottom of the air router 620 adjacent the tank's working air outlet 612. The clean air passage 804 provides a path for relatively liquid- and soil-free air to pass to the vacuum fan 324. A portion of the clean air passage 804 may be formed by a rear cover 640 that is affixed to the back of the air router 620.

The float assembly comprises a buoyant float 624, which may comprise any structure that will tend to float on liquid that accumulates in the recovery tank 108. The float 624 preferably is a hollow air-filled plastic chamber, but it may also be a naturally buoyant material (such a closed-cell foams), or an inverted cup-like structure. The float 624 is attached to a float linkage 626, which is captured between the air router 620 and diverter 622 such that it is free to move vertically, but otherwise generally constrained from movement. The door 628 is pivotally attached to the air router 620 below the clean air passage inlet 626, and can rotate to cover the inlet 626. The float linkage 626 is provided with an actuating pin 642 or other structure that is positioned to press on and close the door 628 when the float 624 rises on liquid in the recovery tank 108. In addition, the door 628 may be provided with a spring or weight to bias the door open, which may be useful to re-open the door against the suction force of the vacuum should the door 628 close before the tank is full. The shape and size of the float 624, float linkage 626 and door 628, as well as the float's buoyancy, can all be adjusted to close the door 628 when the liquid level in the recovery tank 108 reaches its desired fill point, as will be appreciated by those of ordinary skill in the art in view of the present disclosure.

A preferred relationship between the recovery tank 108, its internal assembly 619, and the base assembly 102 and its internal parts is shown in more detail in FIG. 7. Here it is shown that the internal assembly 619 fits within the upper portion of the recovery tank 108 with the dirty air passage inlet 630 positioned adjacent the working air inlet 610 and the clean air passage outlet adjacent the working air outlet 612. The recovery tank 108 fits within the recovery tank pocket 368 in the upper housing 302, and the pocket 368 is provided with first and second apertures 702, 704 that line up with the tank's working air inlet 610 and outlet 612, respectively. When base assembly 102 is fully assembled, these first and second apertures 702, 704 also align with the outlet opening 364 of the inlet air conduit 358, and the inlet passage 332 to the vacuum fan assembly 322. Various seals (not shown), such as labyrinth seals, rubber gaskets, silicone layers, and the like, can be placed between the outlets, inlets and apertures to improve air containment, as will be understood by those of ordinary skill in the art. For example, a foam pad having cutouts corresponding to the apertures 702 and 704 may be positioned on the upper surface of the upper housing 302 within the recovery tank socket 368 to provide a seal between the recovery tank 108 and the rest of the device.

The working air flow path through the recovery tank 108 and its various components is shown in FIG. 8. Working air from the cleaning head 110 (FIG. 1), containing recovered liquid, soil and debris, enters a handle passage 806 in the hollow handle pivot 386 by way of the vacuum hose 112 (FIG. 1), as shown by arrow A. The working air exits through a handle passage outlet 808, which abuts the inlet opening 362 of the inlet air conduit 358. The working air then passes through the enclosed passage in the inlet air conduit 358, as shown by arrow B. The working air exits the inlet air conduit 358 through the outlet opening 364, and passes through the dirty air passage 802, as shown by arrow C. The downwardly-curved exit 634 of the diverter 622 (which forms the end of the dirty air passage 802), directs the working air down into the main reservoir 810 of the recovery tank 108. From here, the working air flow must reverse its direction, as shown by arrow D, in order to exit through the clean air passage 804, which is located above and behind the exit of the dirty air passage 802. This reverse in direction, as well as the rapid increase in cross-sectional area that the airflow path experiences as it exits the dirty air passage 802, contribute towards separating the liquid and entrained soil and debris from the working air. After depositing much or all of the entrained liquid and debris in the recovery tank's main reservoir 810, the working air flows back into the clean air passage 804, which directs the air into the inlet passage 332 of the vacuum motor assembly 322, as shown by arrow E. When the fluid level in the main reservoir 810 rises to a predetermined level, the float 624 rises far enough to push the door 628 closed (or close enough to being closed that the vacuum shuts the door 628). When the door 628 closes, the change in the pitch of the vacuum motor should alert the user that the device is full. However, the door 628 or float assembly may be provided with a visual level indicator to show the amount of fluid in the recovery tank 108, or at least show when the door 628 is closed. For example, an arm 629 may be provided on the door 628 such that it is visible through the upper wall of recovery tank half 604. The recovery tank half 604 may also be provided with graduation lines 631 that act as a scale for the arm 629 to indicate the fluid level within the recovery tank 108.

Referring now to FIGS. 9 and 10, an embodiment of a cleaning head 110 of the present invention is shown in more detail. The cleaning head 110 comprises a hand-operable device that is attached to the base assembly 102 by way of a vacuum hose 112. The vacuum hose 112 may comprise any flexible hose that is suitable for conveying a fluid-laden working air flow. As noted before, the vacuum hose 112 preferably contains within it a hose 902 for conveying liquid from the supply tank 106 to the cleaning head 112, but the liquid hose may instead be external to the vacuum hose 112.

The vacuum hose 112 may be permanently attached to the cleaning head 110 (i.e., attached such that it can not be readily removed during regular use), but preferably is selectively removable from the cleaning head 110. To this end, the vacuum hose 112 terminates at a hose cuff 904 that can be easily attached to and removed from the cleaning head 110. The hose cuff 904 includes a hose connection sleeve 906 over which the vacuum hose 112 slidably fits, and a vacuum connection sleeve 908, which is adapted to slidably fit over a corresponding sleeve 910 in the cleaning head 110. The vacuum connection sleeve 908 has a hole 912 therein, which is positioned to receive a resiliently biased pin 914 on the cleaning head connection sleeve 910 to hold the two in engagement until the pin 914 is pushed out of the hole 912. When the vacuum connection sleeve 908 and the corresponding cleaning head sleeve 910 are engaged, they form a continuous enclosed passage through which the working air can pass to the vacuum hose 112.

In order to connect the liquid hose 902 to the cleaning head 110, the hose cuff 904 is also provided with a female fluid coupler 916, which is retained in place under a cover 918. The liquid hose 902, which is elsewhere contained within the vacuum hose 112, passes through an opening 920 in the hose cuff 904, and is attached to an appropriate fitting 922 on the female fluid coupler 916. The female fluid coupler 916 is positioned such that it slides over a male fluid coupler 924 contained within the cleaning head 112 when the vacuum connection sleeve 908 is engaged. One or both of the female and male fluid couplers 916, 924 may be provided as dry-break fitting that prevents fluid flow therethrough when not attached to the other coupler.

Using this arrangement, the cleaning head 112 can be easily disconnected from the vacuum hose 112 by simply pressing the pin 914 inwards and separating the parts. While this embodiment is preferred because it allows simple, simultaneous attachment of the vacuum and liquid lines, other embodiments may also be used. For example, a bayonet-type fitting or other type of removable attachment may instead be used for the vacuum attachment, and a separate dry-break attachment may be provided for the liquid hose, and so on.

The cleaning head 110 generally comprises a handle 926, a trigger 928, a mixture control 930, an auxiliary supply tank 932, and an inlet nozzle 934. The handle 926 is shaped to be gripped by a user to control the cleaning head, and the trigger 928 and mixture control 930 are preferably provided within easy reach of the handle 926, such that they can be manipulated without removing one's hand from the handle 926. The trigger 928 is positioned to operate a flow valve 936, and the mixture control 930 operates a diverter valve 938. Both valves 936, 938 are contained within the cleaning head 110. The operation of the valves is described elsewhere herein with respect to FIG. 11.

The auxiliary supply tank 932 may be removable from the cleaning head 110, or may be permanently attached thereto. The auxiliary supply tank 932 is provided to contain detergent or other desirable chemical treatments. In a preferred embodiment, the auxiliary supply tank 932 comprises a generally enclosed chamber having a cover 940 that seals a refill opening 942 on top of the tank. The cover 940 is similar to the supply and recovery tank covers 408, 616, and may be provided with a pin that fits into a corresponding hole to retain the cover 940 when it is not sealing the opening 942. The auxiliary supply tank 932 or its cover also may have a vent hole (not shown), such as those described elsewhere herein. The auxiliary supply tank 932 has an outlet 948 that is sealed by a dry-break valve 950, such as those described herein or of similar construction, that seals the auxiliary supply tank 932 when it is removed from the cleaning head 110. The dry-break valve 950 engages with a corresponding auxiliary supply tank fluid connector 952 in the cleaning head 110 to open a fluid path when the auxiliary supply tank 932 is installed.

The auxiliary supply tank fluid connector 952 is fluidly connected to an eductor 954, the operation of which is described elsewhere herein, or any other type of fluid mixing device. This connection preferably includes a check valve that prevents fluid from escaping out of the fluid connector 952 when the auxiliary supply tank 932 is removed. In one embodiment, the check valve may comprise a rubber plug 956, a spherical plug (ball bearing), thin film, or the like, that is biased by a spring 958 to cover the exit 960 of the fluid connector 952. This arrangement allows fluid to flow from the auxiliary supply tank 932 to the eductor 954, but not in the other direction. Of course, other check valves may be used instead, or the check valve may be omitted. While the eductor 954 is shown below the auxiliary supply tank fluid connector in FIG. 10, in a more preferred embodiment it is located near the top of the cleaning head 110 between the flow valve 936 and the diverter valve 938. This arrangement has been found to help prevent the contents of the auxiliary supply tank from siphoning out when the flow valve 936 is turned off.

It has been found that placement of the auxiliary supply tank 932 in the cleaning head 110 provides numerous advantages over systems in which the auxiliary supply tank is contained in the base assembly 102 or is pre-mixed with the water in the supply tank 106. One advantage is that the flow of detergent can be nearly instantaneously stopped, allowing for rapid switches between the washing mode of operation, in which water and detergent are applied to the surface being cleaned, and the rinsing mode of operation, in which only clean water from the supply tank 106 is deposited. This is possible because the detergent only passes through a relatively short section of tubing before being deposited, preferably less than about six inches, and therefore it can be rapidly purged from the system when it is no longer desired. Another advantage of the present invention is that the auxiliary supply tank 932 can be quickly replaced by another tank having an additional cleaning fluid or a different or complementary chemical treatment. For example, the device may be provided with multiple cleaning tanks 932, each of which has a detergent specially selected to treat particular types of stains or soil. In an embodiment in which multiple auxiliary supply tanks 932 are provided, the base assembly 102, handle 104, cleaning head 110, hose 112 or other parts of the device may be provided with pockets, clips or other mounting structures to hold the tanks that are not currently being used. For example, a storage pocket 114 may be provided on the base assembly 102, as shown in FIG. 1.

In another embodiment of the invention, the cleaning head 110 may have multiple auxiliary supply tank receptacles 990, each of which receives a separate auxiliary supply tank 932. Each of the tanks 932 is plumbed into the fluid system, and a user can operate a valve to elect which tank is to be used at a given time. This allows the user to quickly select from among several different fluids to mix and apply to the surface being cleaned. In another embodiment, the auxiliary supply tank 932 itself may be partitioned into multiple separate compartments, each of which is separately fluidly connected to the cleaning head (such as by separate dry-break connectors). This provides a more compact system in which the user can select which tank (and its associated contents) to use at any given time. For example, the tank 932 may contain separate compartments (FIG. 15) for detergent, stain remover concentrate, fabric protector, and the like.

The inlet nozzle 934 of the cleaning head 110 is formed as a narrow slit between a nozzle cover 962 and a nozzle base 964. The nozzle cover 962 preferably is removable from the nozzle base 964, and may be pivotally attached thereto by pins 966 that fit into corresponding holes 968. A projection 970 on the nozzle base 964 snaps into a corresponding notch (not shown) in the nozzle cover 962 to hold it in place during operation. The nozzle base 964 and nozzle cover 962 form a narrow slit-like passage that extends upwards from the surface being cleaned to a main vacuum passage 972 that extends back to the sleeve 910. Thus, it will be seen that, when the hose cuff 904 is attached to the cleaning head 110 and the recovery tank 108 is installed in the base assembly 102, a continuous working air passage is formed between the inlet nozzle 934 and the vacuum fan 324.

The cleaning head 110 may also include a brush 980 that may be permanently or selectively attached near the nozzle base 964 to provide the user with a means for manually agitating the surface. The brush 980 may also be replaced by a powered brush of any known type, as are known in the art. The brush may also be replaced by an ultrasonic cleaning implement that agitates the surface with ultrasonic waves to enhance the cleaning operation. Such devices are known in the art and described, for example, in U.S. Pat. Nos. 6,276,444 and 4,069,541, which are incorporated herein by reference.

In the embodiment of FIG. 10, the main vacuum passage 972 and nozzle base 964 are formed as a single part that is installed between two cleaning head housing halves 974, 976. These halves 974, 976 also encase the remaining non-removable parts of the cleaning head 110. For example, the trigger 928 is held between the halves 974, 976 such that it pivots on a pair of bosses 978. The halves 974, 976 also contain the male fluid coupler 924 for the vacuum hose, the auxiliary supply tank fluid connector 952, the eductor 954 and the check valve. In addition, the flow valve 963 is held in place such that it is actuated by the trigger 928, and the diverter valve 938 is held with its slide control 930 in a slot 982. The halves 974, 976 also contain one or more sprayers 984 that are positioned to direct the water and detergent downward onto the surface being cleaned. The hoses connecting the various fluid-conveying parts are also contained between the cleaning head housing halves 974, 976.

In the shown embodiment, the cleaning head 110 has two sprayers 984 that are held in corresponding cradles 986 on opposite sides of the main vacuum passage 972, and are oriented to spray through respective spray openings 988 through the bottoms of the cleaning head housing halves 974, 976. While the term sprayer is used generally herein, it will be understood that such sprayers need not forcibly eject the fluid therefrom, and instead may operate by slowly depositing the fluid or “dribbling” the fluid onto the surface being cleaned or otherwise expelling the fluid on the surface. The two sprayers 984 may be provided separately, but in a preferred embodiment they are conjoined as a single part (see FIG. 11). It is preferred to orient the sprayers to direct their flow in an even pattern that is centered along the centerline of the cleaning head 110. In embodiments in which both sprayers 984 are used simultaneously, the sprayers 984 may be aimed to direct their patterns in two streams that strike the target surface on opposite sides of the centerline, with relatively little or no overlap. If the sprayers 984 are intended to operate separately, as described herein with reference to FIG. 11, or of only one sprayer 984 provides water or detergent, then the sprayers 984 preferably are aimed to each generate a spray pattern that is centered on the centerline of the cleaning head 110 (understanding, of course, that the actual point of impact will vary depending on the manner in which the cleaning head 110 is held relative to the surface being cleaned). In this embodiment, the sprayers 984 have significantly overlapping spray patterns.

The cleaning head housing halves 974, 976 also form an auxiliary supply tank receptacle 990. The auxiliary supply tank receptacle 990 preferably is shaped to slidably receive the auxiliary supply tank 932, and has cut-back ends 992 that allow a user to grasp the sides of the auxiliary supply tank 932 for removal. The auxiliary supply tank receptacle 990 is tilted downward towards the back of the cleaning head 110 so that the contents of the auxiliary supply tank 932 tend to flow down towards the dry-break valve 950 and auxiliary supply tank fluid connector 952 when the cleaning head 110 is held horizontally, as during normal use. The auxiliary supply tank receptacle 990 also preferably has an open rear portion 994 (which may be open or covered with a transparent window) to allow the user to see the auxiliary supply tank 932. When such an opening 994 is provided, the auxiliary supply tank 932 may have a transparent window (or be made entirely of a transparent material), that aligns with the opening 994 so that a user can check the contents of the auxiliary supply tank 932.

While the foregoing auxiliary supply tank receptacle 990 is preferred, it is also envisioned that the receptacle may take other configurations, and need not be adapted to slidably receive the auxiliary supply tank 932. For example, the auxiliary supply tank receptacle may instead comprise a threaded or bayonet-type receiver for receiving corresponding portion of the auxiliary supply tank, or may be an internal compartment that is accessed by a door, and so on. Other variations will be apparent to those of ordinary skill in the art in view of the present disclosure and with further practice of the invention.

FIG. 11 illustrates a preferred fluid flow schematic for the cleaning head 110 of the present invention. In this embodiment, pressurized fluid is transported to the cleaning head by way of a main supply 1102, such as the fluid hose 902 (FIGS. 9 and 12) from the supply tank 106 and fluid pump 312. The main supply 1102, as well as other fluid conduits described herein (such as conduits 1114, 1124, 1128 and 1136), preferably comprises a silicon rubber hose, polyvinylchloride (PVC), or other flexible tube. The main supply 1102 conveys the pressurized fluid to the inlet 1104 of the flow valve 936, which is selectively controllable, such as by trigger 928 (FIG. 10), to allow the fluid to pass out of the flow valve's outlet 1110. In a preferred embodiment, the flow valve 936 comprises a plunger 1106 that is depressed to slide an annular seal 1108 to a point where a flow path is created between the inlet 1104 and the outlet 1108. A spring 1112 is provided to bias the plunger 1106 and annular seal 1108 back to block the flow path when the flow valve 936 is not being actuated. This is the valve's off position. While such a plunger valve is preferred, other valves, such as a rotary valve or ball valve, may instead be used as the main flow valve 936 to control the source of pressurized fluid. The flow valve 936 may also comprise a simple pinch valve that compresses the main supply line 1102 until it is closed to stop fluid flow. In addition, the flow valve 936 may be provided as a two-position valve that allows either full flow or no flow, or may be provided to allow multiple operating positions in which the flow rate is selectively controllable between no flow, full flow rate, and one or more intermediate flow rates.

The pressurized fluid passing out of the flow valve 936 is conveyed via a conduit 1114 to the inlet of the diverter valve 938. The diverter valve 938 preferably comprises a two-way valve that directs the pressurized fluid to either a first outlet 1122 or a second outlet 1126, depending on the position of an annular seal 1120 located within the valve 938. The annular seal 1120 is actuated by the mixture control switch 930 by way of a plunger 1118 or other armature or linkage. While the shown diverter valve 938 is a binary valve—that is, it only passes fluid in one of the two outlets at any given time—it is also envisioned that the diverter valve 938 may be provided as a proportional valve that allows fluid to be passed through both outlets at the same time, but in varying proportional amounts.

When the mixture control 930 is positioned to direct the pressurized fluid through the first diverter valve outlet 1122, the pressurized fluid is conveyed through conduit 1124 directly to a first sprayer 984′. In this position (which is illustrated in FIG. 11), the pressurized fluid is not mixed with any other fluid before it is deposited onto the surface being cleaned. As such, when water is used as the pressurized fluid, this corresponds to the rinsing mode of the machine. Alternatively, when the mixture control 930 is adjusted to divert the pressurized fluid through the second diverter valve outlet 1126, the pressurized fluid is processed to mix additional cleaning fluid (or other chemicals) into it. This mode is generally referred to as the washing mode.

In the washing mode, the pressurized fluid is conveyed through conduit 1128 to the inlet 1130 of the eductor 954. The eductor 954 comprises a main inlet 1130, an outlet 1132, a suction inlet 1138, and a constriction 1134 between the main inlet 1130 and the outlet 1132 and suction inlet 1138. The constriction, like in conventional known eductors, comprises an area of reduced cross-sectional area where the fluid momentarily accelerates as it passes through the eductor. As the fluid exits the constriction 1134, it creates a suction force that draws fluid in from the suction inlet 1138, which then mixes with the main fluid supply. In this manner, a detergent or other cleaning fluid can be introduced into the main fluid supply. The use of such eductors to mix detergent into a main cleaning fluid is known, and described, for example, in U.S. Pat. No. 4,333,203, which is incorporated herein by reference. While the shown eductor 954 is fixed (that is, its geometry can not be varied to change the ratio of the fluid mixture), it may instead be adapted to have a variable profile, as in U.S. Pat. No. 4,333,203 or in other known ways.

While a supply of detergent or other cleaning fluid can be provided to the eductor's secondary inlet 1138 by any system of reservoirs and hoses, a compact and efficient fluid system is provided by the embodiment of FIGS. 10 and 11. In this embodiment, the auxiliary supply tank 932 is provided with a dry-break valve 950 that fits, by friction, adhesive or other attachment, into a lower portion of the auxiliary supply tank 932 (that is, a portion of the auxiliary supply tank 932 that is expected to typically be in the lowest location during regular use of the cleaning head 110). The dry break valve 950 preferably comprises a tank fitting portion 1140 that fits into and seals against an opening in the auxiliary supply tank 932, and has a central passage therethrough into which the auxiliary supply tank fluid connector 952 fits. An o-ring or other seal is provided to prevent or minimize fluid leaking past the auxiliary supply tank fluid connector 952. The auxiliary supply tank connector 952 is retained in the cleaning head 110 such that it engages the dry break valve 950 when the auxiliary supply tank 932 is inserted into the cleaning head 110 as shown in the embodiment of the previous figures.

The dry-break valve 950 also includes a cage portion 1142 that is formed at the end of the tank fitting portion 1140 or formed separately and attached thereto by bayonet fittings or the like. The cage portion 1142 comprises a structure that allows fluid to pass through it, but has sufficient structure and shape to retain a plunger 1144, plunger seal 1146, and a spring 1148. The plunger 1144 is disposed in the dry-break valve 950 such that it extends into the central passage of the tank fitting portion 1140 into which the auxiliary supply tank fluid connector 952 fits. The plunger seal 1146 is disposed annularly around the end of the plunger 1144, and the spring 1148 biases the plunger 1144 towards the tank fitting portion 1140 (to the right in FIG. 11) and presses the plunger seal 1146 against the tank fitting portion 1140 to thereby seal the auxiliary supply tank 932 closed. When the auxiliary supply tank fluid connector 952 is inserted into the central passage, however, the end of the auxiliary supply tank fluid connector 952 presses the plunger back against the bias of the spring 1148 (to the left in FIG. 11), thereby unseating the plunger seal 1146 and allowing fluid to pass therethrough. This latter configuration is shown in FIG. 11.

The auxiliary supply tank fluid connector 952 may be directly connected to, or formed as part of, the eductor 954, however it is preferred to attaching the fluid connector exit 960 to the eductor's secondary inlet 1138 by a flexible hose 1139. The fluid passage between the auxiliary supply tank fluid connector 952 and the eductor 954 is also provided with a check valve to prevent fluid from passing from the eductor 954 to the auxiliary supply tank 932. The check valve also helps prevent fluid in the auxiliary supply tank 932 from siphoning out through the eductor 954 when the flow valve 936 is closed. The check valve may be of any construction, but preferably comprises a plug 956 that is inserted into the auxiliary supply tank fluid connector 952 itself, and biased against a corresponding sealing surface within the connector 952 by a spring 958. The plug 956 and spring 958 are held in place by abutment with the end of the secondary inlet 1138 of the eductor 954. This configuration has been found to provide a very compact package that can be used in any variety of cleaning heads 110.

As noted before, as pressurized fluid passes through the constriction 1134 of the eductor 954, it draws a certain amount of detergent from the auxiliary supply tank through the secondary inlet 1138, thereby providing a detergent mixture that exits the eductor outlet 1132. The exact proportion of detergent (or other fluid) that is mixed into the pressurized fluid will vary depending upon the size of the eductor constriction 1134 and the secondary inlet 1138, the size of the spray orifices through the sprayer(s) 984, the pressure, viscosity and temperature of the fluids, and various other factors that will be understood or readily determined by those of ordinary skill in the art. In a preferred embodiment, the constriction 1134 has a diameter of about 1.1 mm, the suction inlet 1138 passes through a restriction of about 0.7 mm, and the sprayer 984″ through which the mixture passes has a diameter of about 1.7 mm.

The fluid/detergent mixture leaving the eductor outlet 1132 is conveyed to a second sprayer 984″ via conduit 1136. The second sprayer 984″ preferably is formed as a single part 1150 with the first sprayer 984′. The first and second sprayers 984′, 984″ are each directed to focus their sprays on approximately the same position on the surface being cleaned, so that the spray pattern will be approximately the same regardless of whether the user is operating the device in the rinsing mode or the washing mode.

Having described an embodiment of the fluid supply system in detail, it will now be apparent that the fluid system of the present invention provides a novel system for providing a mixture of cleaning solution (or other chemical) and water to a surface being cleaned, while also allowing the provision of cleaning solution to be quickly cut off to operate using water alone. Furthermore, by positioning the auxiliary supply tank 932 in the cleaning head 110 and bypassing the auxiliary supply tank 932 when rinsing is desired, the rinse mode can be initiated without having to purge the fluid lines of detergent-laden fluid, which saves time and detergent. Other uses and combinations of fluids other than water and detergent may also be used with the present invention, as will also be apparent to those of ordinary skill in the art.

While the fluid circuit shown in FIG. 11 is preferred, variations on this design are also envisioned in the present invention. For example the diverter valve 938 may be omitted, and all of the fluid flow can be directed through the eductor 954 and the second sprayer 984″ to provide a simplified device. In such a simplified device, the rinsing mode can be initiated by simply removing the auxiliary supply tank 932, and the eductor 954 may be located before or after the flow valve 936. If located before the flow valve 936, a check valve may be required to prevent flow into the auxiliary supply tank 932 when the flow valve 932 is shut. The eductor 954 may also be adjustable in such an embodiment (or in the embodiment of FIG. 11) to provide greater control of the mixture ratio. In still another embodiment, the flow valve 936 may be omitted and replaced by an electric switch (not shown) that energizes the pump 312 (FIG. 3) only when spraying is desired.

Referring now to FIG. 12, the wet extractor 100 preferably is provided with one or more handles to facilitate its movement and storage. While such handles may be conventional fixed handles, it is preferred that the handle 104 comprises a pivoting handle, having lowered and raised positions as shown in FIGS. 1 and 2. Such a handle facilitates movement of the device, while still providing some collapsibility to minimize storage space requirements. Preferably, the handle 104 has a hand grip that is located substantially above the center of mass of the device when the handle is in the raised position, so that the device tends to stay level when suspended by the handle 104.

FIG. 12 shows the handle 104 in exploded view. The handle 104 generally comprises a continuous, curved outer handle shell 1202, and an inner handle shell 1204 that fits within the outer handle shell 1202 to provide a more aesthetically pleasing and functional structure. The outer handle shell 1202 is provided with a grip 1206 at its peak, which is retained in place by a grip cover 1208 and suitable fasteners, such as screws 1210 or adhesive. The inner handle shell 1204 is held in place by tabs 1209 that snap into place in slots 1210 in the outer handle shell 1202. Additional tabs 1212 may also be provided on the inner handle shell 1204 to engage with corresponding tabs 1214 on the grip 1206 (or elsewhere near the peak of the outer handle shell 1202), thereby securing the two handle shells together at numerous locations to provide a secure connection.

The inner handle shell 1204 preferably forms a semi-circular passage 1216 into which the vacuum hose 112 nests for secure and partially concealed storage. The semi-circular passage 1216 may also be shaped to envelop the vacuum hose 112 in such a manner that the hose 112 snaps into place within the passage 1216. Hose clips 1218, which are shaped to snap-engage with the hose 112, may also be provided on the handle 104, such as by being captured between the inner and outer handle shells 1202, 1204, or formed integrally with one or both of the handle shells (not shown). One or both of such hose clips 1218 may have multiple clips, such as one of the hose clips 1218 shown in FIG. 12, to hold multiple loops of the hose 112.

The free ends of the outer handle shell 1202 are provided with inwardly-protruding bearing portions 1220 that are shaped to slide over the handle pivot 386. In order to cause the handle pivot 386 to pivot with the handle 104, the bearing portions 1220 have indented portions 1222 that slide into a corresponding indented portion 1224 of the handle pivot. The close sliding engagement between these indentations 1222, 1224 acts as a physical stop to prevent independent rotation of the handle 104 and handle pivot 386.

The outer portions of the handle bearing portions 1220 are surrounded by handle pivot bushings 384, which fit within the pivot holes 382 of the upper extractor housing 302 (see FIG. 3). The handle pivot bushings 384 are cylindrical, and formed of a durable, low-friction material to pivotally join the handle 104 to the extractor. Each bushing 384 may also be slotted to accommodate dimensional variations between the handle bearing portions 1220 and the pivot holes 382 and to provide an escape path for grit or other debris that may work its way to the bearing surface.

As noted before, the handle pivot 386 preferably includes a hollow portion that forms part of the air flow path from the cleaning head 110 to the recovery tank 108. As such, one end of the handle pivot includes a hollow hose fitting 1226 to which the vacuum hose 112 is affixed. The fluid hose 902 also passes through this hose fitting 1226. The hose fitting 1226 extends to the central portion of the hollow handle pivot 386, where it is fluidly connected to the handle passage outlet 808, which abuts the inlet opening 362 of the inlet air conduit 358, as described previously herein with reference to FIG. 8.

The details of the handle pivot construction are shown in more detail in FIG. 13. Here it can be seen that the handle pivot 386 has the hose fitting 1226 at one end, and the handle passage outlet 808 located part-way down the length of the handle pivot 386. The hollow region 1302 between the hose fitting 1226 and the handle passage outlet 808 is subjected to the vacuum generated by the vacuum fan assembly 322. The end of the hollow region 1302 distal from the hose fitting 1226 is sealed by an inner cap 1306. The inner cap 1306 is positioned between the circumferential slot 390 and the handle passage outlet 808, and is provided with a hole 1308 through which the fluid hose 902 passes. The end of the handle pivot 386 opposite the hose fitting 1226 is provided with a barbed periphery 1310, and a number of slots 1312, which allow this end of the handle pivot 386 to be compressed radially inward to snap into the corresponding end of the outer handle shell 1202. It has been found that this construction firmly retains the outer handle shell 1202 on the handle pivot 386 without the need for additional fasters. However, other fastening methods may instead be used.

Referring more specifically to FIG. 14, a seal 1304 is provided on the outer surface of the handle pivot 386 around the periphery of the handle passage outlet 808 to prevent or reduce vacuum leaks at the junction between the handle passage outlet 808 and the inlet opening 362 of the inlet air conduit 358. The handle passage outlet 808 is located such that it is in communication with the inlet opening 362 regardless of the angular orientation of the handle 104. As such, the wet extractor can be used when the handle 104 is raised or lowered.

The extent to which the handle 104 can be raised and lowered is limited by the handle stop 388. The handle stop 388 comprises a base portion 1402 that is rigidly mounted to the extractor housing, and a stop portion 1404 that is shaped to fit within a corresponding indent 1406 of the handle pivot 386. As shown in FIG. 12, this indent 1406 is essentially a continuation of the indented portions 1224 of the handle pivot 386, but may occupy an increased portion of the handle pivot's circumference to provide greater control over the handle pivot's (and hence the handle's) range of rotation. The indent 1406 has, at each circumferential end, a contact surface 1408. These indent contact surfaces 1408 are shaped to squarely abut corresponding contact surfaces 1410 on the stop portion 1404 of the handle stop 388. The total amount of handle rotation, and the locations at which the handle 104 is positioned in its upper and lower positions, can be changed by varying the circumferential size of the indent 1406 and the locations of the contact surfaces 1408, 1410, as will be appreciated by those of ordinary skill in the art in view of the present disclosure. In a preferred embodiment, the indent 1406 and handle stop 388 are shaped such that the handle 104 can rotate about 30 to 60 degrees, and the handle grip 1206 is positioned approximately above the device's center of gravity when the handle 104 is in the raised position.

Referring now to FIG. 15, another embodiment of the fluid deposition system of the present invention is described. In this embodiment, the fluid system is substantially similar to the embodiment of FIG. 11, however, the single auxiliary supply tank 932 of that embodiment is replaced here with a multi-chambered auxiliary supply tank 1502. The multi-chambered auxiliary supply tank 1502 may be integral with the cleaning head, or removable as a separate unit, and has multiple fluidly separate chambers 1504, 1506, 1508. Each chamber 1504, 1506, 1508 preferably is connected by its own dry-break fitting when the tank 1502 is inserted into the cleaning head 110. The fluid outlets of each of the chambers 1504, 1506, 1508 are connected by respective conduits 1510, 1512, 1514 to a three-way selector valve 1516. The selector valve 1516 has three inputs (or one for each chamber, if more or fewer than three are provided), and a central barrel 1518 that can be rotated by an appropriate control to place any one of the inputs into fluid connection with the selector valve's outlet 1520. The opening of the barrel 1518 may also be wide enough to receive the input of two adjacent inlets simultaneously, if desired. A conduit 1522 connects the selector valve outlet 1520 to the suction inlet 1138 of the eductor. Using this embodiment, the device can quickly switch between multiple different solutions to mix with the main fluid supply, such as detergent, stain remover concentrate, fabric protector, and the like.

Variations on the embodiment of FIG. 15 will also be apparent to those of ordinary skill in the art. For example, the selector valve 1516 may comprise any other type of valve, and is not limited to being the shown barrel valve. Also, the single, multi-chambered auxiliary supply tank 1502 may be replaced by multiple separate tanks. Also, each chamber (or separate tank) may have a dedicated flow control valve to allow for more complex combinations of solution mixtures. Each chamber (or separate tank) may also have its own eductor or other mixing device, and may have its own sprayer for depositing the mixed fluid.

Another aspect of the present invention is to provide a pressure relief system to reduce dead head pressures that occur when the flow valve 936 is closed. During such conditions, if the pump continues to operate it will do so without moving any fluid, and may overheat. One solution to this is to electrically disconnect the pump when the flow valve 936 is closed. In such an embodiment, the electrical contacts may be operated by a temperature sensor that detects excessive heat build up in or around the motor 316, a pressure sensor, an electrical switch associated with the flow valve 936, and so on. As noted before, the flow valve 936 may also simply be replaced by an electrical switch that initiates and stops flow by activating and deactivating the pump 316. Such an electrical switch may be operated through a step-up transformer, “MOSFET,” operational amplifier or other circuitry to reduce the electrical current level in the wires leading to the electric switch used as the flow valve 936 to a degree that minimizes the risk of injury by electric shock.

Another dead head prevention system is illustrated in FIG. 16, which is a schematic representation of an embodiment of the fluid pumping system having a bypass circuit that opens when the flow valve 936 is closed. In this embodiment, the device comprises the supply tank 106, fluid pump 312 and main fluid supply hose 902 that leads to the flow valve 936 in the cleaning head 110 (not shown). The fluid pump 312 comprises an electric motor 316, preferably a 120 volt AC motor, that drives a centrifugal pump 318, fan pump, impeller or other type of hydraulic pump. Fluid from the supply tank 106 is conveyed by a conduit 1602 to a first T-fitting 1604, and from there to the inlet of the fluid pump 312 by way of an pump inlet conduit 1606. The fluid pump 312 pressurizes the fluid and pushes it through a pump outlet conduit 1608, where it passes into a second T-fitting 1610. The second T-fitting passes the pressurized fluid to the main supply fluid hose 902 and to a bypass inlet conduit 1626.

The bypass inlet conduit 1626 serves as the entry point into the inlet side 1622 of a bypass valve 1612. The bypass valve 1612 may be any type of pressure relief valve that is closed at normal operating pressures, but opens when the pressure exceeds normal levels, as may occur when the flow valve 936 is closed but the fluid pump 312 remains operational. In the present exemplary embodiment, the bypass valve 1612 comprises a piston 1616 that fits within the bore of a cylinder 1620 such that it can slide along the cylinder's axis. A spring 1618 biases the piston 1616 against the flow of pressurized fluid, and a seal 1614 is provided on the piston 1616 at its downstream end to abut the end of the cylinder 1620 and seal the circuit. A bypass valve inlet 1622 is provided to receive pressurized fluid from the bypass inlet conduit 1626, and a bypass valve outlet 1624 is provided to fluidly connect to the first T-fitting 1604 by way of a bypass outlet conduit 1628.

During use, when the flow valve 936 is open, the pressurized fluid from the fluid pump 312 is free to flow through the main supply hose 902, and the pressure in the bypass inlet conduit 1626 remains relatively low. Under these conditions, the spring 1618 presses the piston 1616 towards the bypass valve inlet 1622 and the seal 1614 abuts the cylinder 1620 to prevent fluid from passing through the bypass valve 1612. When the flow valve 936 is closed, however, the pressurized fluid does not have a ready escape path, and the pressure in the bypass inlet conduit 1626 increases. When this occurs, the pressure in the fluid overcomes the bias of the spring 1618 and forces the piston along the direction of flow to unseat the seal 1614 and open the bypass valve 1612, as shown in FIG. 16. With the bypass valve open, the pressurized fluid is free to circulate back into the pump inlet conduit 1606. This reduces the dead head pressure experienced in the system, particularly at the flow valve 936, which can improve the durability and leak resistance of the device. Furthermore, allowing fluid circulation when the flow valve 936 is off reduces heat buildup in the fluid, fluid pump 312, and adjacent parts. This feature also may help protect the device in the event that the fluid flow path becomes obstructed by foreign matter. The lengths of the pump inlet conduit 1606, pump outlet conduit 1608, bypass inlet conduit 1626 and bypass outlet conduit 1628 can be increased to provide more heat dissipation when the bypass valve 1612 is open, and one or more of the parts or conduits may be provided with (or pass through) cooling vanes or other heat-dissipating structures. Those of ordinary skill in the art will be able to adjust the spring rate and other features of the bypass valve 1612 to provide suitable results without under experimentation.

Also shown in FIG. 16 is another feature of an embodiment of the invention, which is a pump priming assembly 1632. The priming assembly 1632 may be provided to vent air out of the various conduits to allow fluid from the supply tank 106 to flow into the pump 318. This is useful when the pump 318 is unable to self-prime, as in the case of common centrifugal pumps. The priming assembly 1632 comprises a wall 1634 (preferably cylindrical) that forms a chamber 1636 in which a float 1638 resides. The float 1638 may be any buoyant object, such as an enclosed capsule having an air pocket therein (as shown), a block of substance having a negative buoyancy, or an inverted cup-like object that can rise on a pocket of air captured beneath it. The float 1638 is sized such that it freely slides up and down within the chamber 1636, but is small enough that air can pass between the float 1638 and the wall 1634. The chamber 1636 also includes a vent 1640 located at its upper extremity. An upper surface of the float 1638 is adapted to block the vent 1640 when the float 1638 is at the top of its travel. The vent 1640 preferably is connected, by way of a hose (not shown), to the collecting trough 305 (FIG. 3), so that any fluid that might seep out of the vent is safely removed from the base housing assembly 102 and thereby reduce the risk of presenting an shock hazard.

The priming assembly 1632 is spliced into the pump outlet conduit 1608 (or may be spliced into the fluid hose 902), by a T-fitting 1630. When the fluid system is empty (dry) and the supply tank 106 is attached to fill the system, fluid from the supply tank 106 flows into and through the pump 318 by gravity, then into the priming assembly chamber 1636. The force of the fluid drives air in the system through the conduits and pump to the priming assembly chamber 1636, where it escapes around the float 1638 and through the vent 1640. The fluid also eventually enters the chamber 1636, and lifts the float 1638 until it blocks the vent 1640, at which point the pump 318 is primed with fluid and the device is ready for operation. The chamber 1636 is preferably located such that the vent 1640 is as high as possible within the base assembly 102, which minimizes the amount of hydraulic pressure applied at the seal formed between the float 1638 and the vent 1640, thereby reducing the possibility of developing a leak at this seal. While this priming assembly is preferred, it will be understood that other priming assemblies (or check valves or the like) may be used with the present invention to ensure that the pump is properly primed, if necessary.

Referring now to FIGS. 17-19, an alternative embodiment of a hose and handle arrangement of the present invention is shown and described. As shown in FIG. 17, the handle 1700 is a pivoting handle similar to the handle described with reference to FIG. 12. In this embodiment, the handle 1700 comprises an outer handle shell 1702, an inner handle shell 1704, a grip 1706, hose clips 1718, and various other features as in the embodiment of FIG. 12. The primary differences between the embodiments of FIG. 17 and 12 are in the construction of the ends of the outer handle 1702 and the handle pivot 1708, and the manner in which the vacuum hose 112 operates with the handle 1700.

In this embodiment, the pivot bushings 384 are removed, and the ends of the outer handle 1702 are shaped with inwardly-extending pivot structures 1720. FIG. 18 shows, in cross-section, how these pivot structures 1720 fit in the base assembly 102. As can be seen in FIG. 19, the pivot structures 1720 each comprise a generally circular shape having a segment removed therefrom to form a cutout portion 1802. The pivot structures 1720 fit within a generally circular hole 1804 in the base assembly 102. Each circular hole 1804 has a travel stop 1806 formed therein. The travel stop 1806 is a rigid structure that extends into the circular perimeter of the hole 1804. The travel stop 1806 is smaller than, and positioned within, the cutout portion 1802 of the handle's pivot structures 1720, thereby allowing limited rotation of the pivot structures 1720 within the circular holes 1804. It has been found that this arrangement allows the handle 1700 to pivot relative to the base assembly 102, but provides a strong positive retention force at each end of the handle's travel.

As with the embodiment of FIG. 12, the handle pivot 1708 fits within the ends of the outer handle shell 1702, and extends through the pivot structures 1720. Flexible snaps 1722 hold the handle pivot 1708 in the pivot structure 1720, and an end cap 1724 is provided to positively lock the handle pivot 1708 in place. In this embodiment, the vacuum hose 112 extends through the handle pivot 1708, rather than being attached to a hose fitting 1226, as in the embodiment of FIG. 12. To accomplish this, the handle pivot 1708 is provided with a first opening 1726 at one end, and a second opening 1728 located on the shank of the handle pivot 1708. The openings 1726, 1728 are large enough that the vacuum hose 112 can be slid into the first opening 1726 and fed back out of the handle pivot 1708 through the second opening 1728. (Note that the vacuum hose 112 is shown removed for clarity of illustration along a portion of its length where it passes through the handle pivot 1708.) In another embodiment (not shown) the vacuum hose 112 may instead be severed and attached to suitable hose fittings at the first and second openings 1726, 1728, so that it does not pass through the handle pivot 1708.

Referring now to FIGS. 17 and 19, once the vacuum hose 112 is fed through the handle pivot 1708, it is secured with a series of concentric corrugations that mate with corresponding concentric rings formed on the receiving end of conduit 1730, and may optionally be further secured by a cable tie 1732. Of course, any other suitable attachment may be used. FIG. 19 demonstrates how the vacuum hose 112 of FIG. 17 is connected to the working air flow path of the device. This embodiment is similar to the embodiment of FIG. 8, however the inlet air conduit 358 is replaced by the conduit 1730, and the vacuum hose 112 extends into the base housing 102 through a the second opening 1728 in the hollow handle pivot 1708. This arrangement eliminates the need for a seal between the handle passage outlet 808 and the inlet opening 362 of the inlet air conduit 358, as required in the embodiment of FIG. 8. The liquid hose 1734 passes from the pump priming assembly (FIG. 16) to the interior of the vacuum hose 112 by way of an opening 1902 through the side wall of the conduit 1730, which also simplifies the construction relative to the embodiment of FIG. 12. Opening 1902 is smaller in diameter than flexible fluid hose 902, thereby providing a liquid- and air-tight seal around the hose at it exits the opening 1902. The remainder of the devices shown in FIG. 19 are substantially identical to the embodiment of FIG. 8.

Another embodiment of the present invention is shown schematically in FIG. 20. In this embodiment, the invention provides a wet extractor 2000 having convection heating arrangement that can be used to maintain or increase the temperature of a fluid in its supply tank. The wet extractor 2000 comprises a base assembly 2002 into which a supply tank 2004 releasably fits. The supply tank 2004 sits in a pocket 2006 that is preferably contoured to generally match the bottom of the supply tank 2004. Located in the base assembly 2002 are a vacuum fan 2008 and its associated motor 2010. The motor 2010 has a cooling fan 2012, which is adapted to create a flow of air over the motor 2010 to keep it at a desirable operating temperature.

The base assembly 2002 has a motor cooling air flow path that extends from an inlet grille 2016 to an exhaust grille 2018. In the shown embodiment, the cooling air flow path is generally contained within an isolated conduit 2014 within the housing that forms the base assembly 2002. One or more filters or sound mufflers (not shown) may be located in the conduit 2012. The motor 2010 and its cooling fan 2012 are located in the cooling air conduit 2012, and the cooling fan 2012 generates a cooling air flow that draws ambient air in through the inlet grille 2016, passes over and cools the motor 2010, and exits the base assembly 2002 through the exhaust grille 2018, as shown by the dashed arrows. The conduit 2014 may also have other heat-generating parts located in it, such as a pump motor (not shown) or a cord reel (not shown). While the motor's cooling air flow path is shown as being contained in a continuous, enclosed conduit 2014, this particular construction is not required for the present invention. The motor cooling path may instead simply comprise the interior space of the base assembly 2002, or be formed only in part by specific internal conduits.

The conduit 2014 is located within the base assembly 2002 such that it abuts one or more walls that form the supply tank pocket 2006. In this manner, heated air from the motor 2010 can be used to heat fluid 2024 in the supply tank 2004. To enhance the heat transfer between the warmed air in the conduit 2014 and the fluid 2024, the wall 2026 between the conduit 2014 and the pocket 2006 may be formed with (or have located thereon) one or more heat transfer enhancing surfaces. These surfaces may be relatively highly thermally conductive surfaces 2020, such as those described above with respect to FIG. 3. For example, the surfaces 2020 may comprise metal plates that are attached to or embedded within plastic walls that form the supply tank pocket 2006. Additional heat transfer enhancing conductive surfaces 2022 may be provided in or on the wall of the supply tank 2004, as described herein with reference to FIG. 4. When the supply tank 2004 is installed in the pocket 2006, the conductive surfaces 2020, 2022 are in close proximity or abut one another to provide a heat conduction path directly between the cooling air conduit 2014 and the fluid 2024. The conductive surfaces 2020, 2022 may also be provided with heat sink structures (not shown), such as vanes, that protrude into the cooling air conduit 2014 or supply tank 2004 to enhance the heat transfer characteristics to and from the conductive surfaces 2020, 2022.

The base assembly 2002 may also include a door (not shown) that can be actuated to partially or wholly close off the cooling air conduit 2014 and simultaneously open a separate exhaust grille (not shown), or divert the airflow to the exhaust grille 2018 without passing through the cooling air conduit 2014. Such a door could be a manually-operated door that provides the operator with control over how much heat is transferred to the fluid 2024, or may be operated automatically by a control system that detects and regulates the temperature of the fluid 2024 in the supply tank 2004.

While the use of abutting conductive surfaces 2020, 2022 on the supply tank 2004 and the pocket 2006 is preferred, it may be desirable to omit the conductive surfaces 2022 on the supply tank 2004 if such surfaces may cause an undesirable reaction with the fluid 2024. Locating the surfaces 2022 on the exterior surface of the supply tank 2004 (such as by using a foil or deposited conductive layer on the exterior surface of the supply tank 2004), may also resolve any compatibility issues between the thermally conductive surfaces and the fluid 2024. Furthermore, it is believed that even if no conductive surfaces are provided, sufficient heat can be transferred from the motor 2010 to the fluid 2024 to keep the fluid 2024 at an elevated temperature for an extended period. For example, if a user places hot water into the supply tank 2004, then heat from the warm air in the conduit 2014 may be sufficient to maintain the temperature of the hot water within a few degrees Fahrenheit of the starting temperature for a time long enough to permit use of the device. Variations of these embodiments will be readily understood by those of ordinary skill in the art in view of the present disclosure, for example, the features of this embodiment may be used with an upright wet extractor.

A temperature sensor may also be provided to indicate the temperature of the fluid in the supply tank 2004. In the embodiment of FIG. 20, the temperature sensor comprises a thermally conductive element 2028, such as a copper or brass screw, that is installed in the side of the supply tank 2004. When the supply tank 2004 is installed in the base assembly 2002, the conductive element 2028 abuts a temperature sensing element 2030, such as a thermocouple, bimetallic switch, mercury switch, and so on. The temperature sensing element 2030 generates a signal, based on the temperature of the conductive element 2028, and this signal is sent to a display 2032 that is visible to the user to indicate the thermal condition of the fluid 2024. The display may be located on the base assembly 2002, or elsewhere, such as on the cleaning head.

In one embodiment, the temperature sensing element 2030 comprises a bimetallic switch that closes when the temperature exceeds a predetermined value, and thereby applies an electrical current to the display 2032, which comprises a light. Such a configuration provides a simple binary display system in which the light is illuminated when the temperature exceeds the predetermined value, and turns off when the temperature drops below this value. Of course, an opposite arrangement, in which the light is illuminated until the predetermined temperature is reached, may be used instead.

In other embodiments, the temperature sensing element 2030 and display 2032 may comprise a graduated (either digital or analog) display system. For example, the temperature sensing element 2030 may be a thermally expanding element or a thermocouple, and the display 2032 may be a graduated scale that graphically depicts the temperature by reference to this scale (e.g., low, medium, high). The display 2032 may also comprise a numerical temperature display that provides the actual temperature of the supply fluid 2024.

In still another embodiment, the temperature sensing element 2030 may simply comprise a thermometer bulb (or a conductive element that leads to a thermometer bulb), and the display 2032 may comprise the graduated portion of the thermometer.

The temperature sensor and display may also be located in or on the supply tank. An embodiment of such an arrangement is shown in FIGS. 1 and 4, in which a temperature sensor 424 is located directly on the side of the supply tank 106. The temperature sensor 424 is preferably located such that it is near the fluid, even when the tank is close to being empty, and is visible when the cleaning head 110 is removed from the base assembly 102, as shown in FIG. 1.

The temperature sensor 424 of this embodiment may comprise any type of thermometer display, such as a conventional thermometer, but preferably comprises a thermochromic patch that changes color as its temperature changes. Such a thermochromic patch may be provided as a separate part or as an ink or paint that is applied to the surface of the supply tank 106. The thermochromic patch may be adapted to change color at a single predetermined temperature, in which case the predetermined temperature would be selected to correspond with the minimum optimal operating temperature of the fluid in the supply tank 106. The thermochromic patch may instead by provided as a composite of several thermochromic materials that change colors at various different temperatures, which will provide a graduated temperature scale. Thermochromic materials are described in detail in U.S. Pat. Nos. 5,997,849 and 6,139,779, which are incorporated herein by reference. Suitable thermochromic materials are available from various suppliers, including H.W. Sands Corp. of Jupiter, Fla., and Chromatic Technologies, Inc. of Colorado Springs, Colo.

Yet another embodiment of the invention is shown schematically in FIG. 21. In this embodiment, the wet extractor 2100 uses an ultraviolet light source, or other non-chemical biocide device, to kill bacteria in the fluid used and recovered by the device, as well as the surface being cleaned. Ultraviolet (“UV”) light is preferred for use with the present invention because certain wavelengths thereof are known to be effective at killing bacteria. For example, so-called “shortwave UV” or “UV-C,” having a wavelength of about 253.7 nanometers (“nm”), is effective at killing many kinds of bacteria. UV light components suitable for use with the present invention are disclosed in U.S. Pat. Nos. 2,738,427; 4,322,291; 5,441,179; 6,077,427; 6,099,799; and 6,469,308, all of which are incorporated herein by reference. Japan Patent Application No. 9-128641 (published May 16, 1997) is also illustrative of devices that can be used with the present invention, and is also incorporated herein by reference.

The embodiment comprises a wet extractor 2100 having a base housing 2102 and a supply tank 2014 releasably contained therein. As with the other embodiments described herein, the supply tank 2104 provides a supply to fluid 2106 to a cleaning head 2108 by way of a fluid supply line 2110. A pump 2120 and priming assembly 2122 are provided to pressurize the fluid 2106 and convey it to the cleaning head 2108. The cleaning head 2108 may be of the type described previously herein, or may simply have a conventional fluid valve 2112 and spray nozzle 2114 arrangement. The cleaning head 2108 is also connected to a vacuum hose 2116, and has an inlet nozzle 2118 for use in recovering deposited fluid and entrained dirt and debris from the surface being cleaned.

A first ultraviolet light 2124 is located adjacent the supply tank 2104, and is oriented to project UV light into the supply tank 2104 when it is installed in the base housing 2102. As such, at least the portion of the supply tank 2104 adjacent the UV light 2124 is preferably transparent or mostly transparent to UV light. A control circuit (not shown) may be provided to automatically activate the UV light 2124, or it may be manually operated. The UV light 2124 may also be active whenever the wet extractor 2100 is on or plugged in, and a switch 2126 may be provided to turn off the UV light 2124 when the supply tank 2104 is not installed. The first UV light 2124 (or a separate UV light) may also be located adjacent the recovery tank to help kill bacteria therein, or may be located along the incoming working air flow path to irradiate recovered fluid that is entrained in the working air flow path. It is also envisioned that a single UV light could be used to kill bacteria in the supply tank 2104 and the recovery tank.

A second UV light source 2128 is provided to project UV light into the fluid as it passes from the supply tank 2104 to the cleaning head 2108. In a preferred embodiment, the second UV light 2128 is located between the pump 2120 and the priming assembly 2122, however other locations are possible without leaving the scope of the invention. The second UV light 2128 is preferably arranged in a sheath around the fluid supply line 2110, which is partially or wholly transparent to UV light. The second UV light 2128 may be operated according to any desired power consumption algorithm (as with all of the other electric devices used in the device), and may be operated only when the pump 2120 is operating. The second UV light 2128 and fluid supply line 2110 are arranged such that the fluid passing through the supply line 2110 is exposed to the second UV light 2128 for sufficient time to kill a desirable amount of bacteria therein.

A third UV light source 2130 is provided on the cleaning head 2108. This UV light 2130 is oriented to direct UV light onto the surface being cleaned, and may also or alternatively direct UV light onto the fluid being emitted from the spray nozzle 2114 (before, while, or after it exits the nozzle). The third UV light 2130 is powered by either a battery or appropriate wiring from the base housing 2102. The third UV light 2130 may be on at all times when the device is on, but is preferably controlled either by a finger trigger (not shown), or by a trigger (not shown) that activates the third UV light 2130 whenever the inlet nozzle 2118 is positioned next to the surface being cleaned.

Variations on the foregoing arrangements of UV lights may be used with the present invention. For example, one or more of the UV lights may be omitted or relocated to a different position. In addition, one or more of the UV lights may be replaced by another non-chemical biocide devices, such as an ozone generator, an ion exchange module, an electrolytic treatment system, or a water filter. For example, an ozone generator can be provided to extend into the fluid in either the supply tank or the recovery tank, or the fluid supply line 2110 may convey the fluid through an ozone generator. Other variations will be apparent by those of ordinary skill in the art in view of the disclosure herein and with routine practice of the invention. The UV light sources or other non-chemical biocide devices may also be used with non-wet extraction devices, such as conventional bag or bagless upright and canister vacuum cleaners. In such embodiments, the non-chemical biocide devices may be adapted to treat the air flowing into the vacuum cleaner, or the chamber and/or filters in which recovered dirt and debris are stored.

The present invention may be used with chemicals that are not conventionally considered detergents, but may still be useful for treating carpets or fabrics to resist stains, reduce mildew, reduce odors, and so on. One such chemical is sodium bicarbonate (baking soda). It is believed that the use of sodium bicarbonate may be useful to assist with cleaning carpets and fabrics. Such a solution also may leave a slight deposit of sodium bicarbonate on the surface being cleaned, which will tend to eliminate odors in the carpet. Furthermore, any sodium bicarbonate that is recovered in the recovery tank 108 will also help reduce odors therein, which is particularly useful when the recovery tank 108 is not thoroughly cleaned between uses.

The sodium bicarbonate can be provided by mixing it with the water in the supply tank 106, or by providing it as a concentrate in the auxiliary supply tank 932. The sodium bicarbonate may also be mixed with other chemical additives, such as perfumes, brighteners, detergents, and so on. The solution may be used in either the cleaning step or in the rinsing step (or in other steps). When it is only desired to reduce odors in the recovery tank 108, sodium bicarbonate can be placed directly therein. When used in the supply tank 106 or recovery tank 108, the sodium bicarbonate may be provided in a powdered, compacted powder, or solid form, or any other suitable form. When used in the auxiliary supply tank, a substantially liquid form (dissolved or as a suspended solid) is preferred to prevent particles from blocking the eductor. One product that may be adapted for use as described herein is sold under the name ARM & HAMMER CARPET AND ROOM DEODORIZER, which is available from Church & Dwight Co., Inc., of Old Fort, Ohio. This product is generally deposited by hand on a carpet, and removed with a conventional dry vacuum cleaner.

The present invention also encompasses the use of sodium bicarbonate in other types of wet extractor, that may or may not include the structural features of the device described herein. For example, it may be used with conventional upright or canister wet extractors. It may also be used as an additive for wet/dry vacuums, which are vacuums that are adapted to pick up fluids, but do not deposit a fluid on the surface being cleaned. Sodium bicarbonate may also be used with vacuums that use liquid to filter the incoming airstream. Other uses will be apparent to those of ordinary skill in the art in view of the present disclosure and with practice of the inventions described herein.

While the present invention has been described and illustrated herein with reference to various preferred embodiments, it should be understood that these embodiments are exemplary only, and other embodiments will be apparent to those of ordinary skill in the art in light of the teachings provided herein. For example, while the foregoing description of the present invention has been described in reference to a portable wet extractor, the inventors have found that the features of the present invention can also be used with a wide variety of products, such as upright and canister style vacuums and extractors of both the wet- and dry-extraction type. For example the inventions herein may be incorporated into an upright wet extractor, such as that shown in U.S. Pat. No. 5,933,912, which is incorporated by reference herein. In such a case, the extractor may comprise a housing that has both a base element and a handle element, and the supply tank, recovery tank, vacuum hose, fluid hose and other parts may be attached to or mounted on or within either the base or the handle portion of the housing, as will be appreciated by those of ordinary skill in the art.

Furthermore, to the extent that the features of the claims are subject to manufacturing variances or variations caused by practical considerations, it will be understood that the present claims are intended to cover such claims. It will also be understood that while the present disclosure identifies and discusses numerous different inventions in relation to the preferred embodiments, the inventions recited in the following claims are not intended to be limited to being used in conjunction with any other inventions described herein unless specifically recited as having such limitations. 

1. A cleaning device comprising: a housing adapted to hold: a first supply tank adapted to contain a first fluid; a recovery tank; a vacuum fan adapted to generate a working air flow through the recovery tank; and a fluid pump having a pump inlet and a pump outlet, the pump inlet being adapted to receive the first fluid from the first supply tank; a hose assembly having a proximal end connected to the housing and a distal end freely moveable relative to the housing, the hose assembly comprising: a vacuum hose in communication with the recovery tank; and a fluid hose in communication with the pump outlet; a cleaning head connected to the distal end of the hose assembly, the cleaning head comprising: an inlet nozzle in communication with the vacuum hose; and a fluid deposition system in communication with the fluid hose, the fluid deposition system comprising: a second supply tank adapted to contain a second fluid, the second supply tank being selectively removable from the cleaning head and comprising a dry-break valve that automatically seals the second supply tank upon removal of the second supply tank from the cleaning head; a fluid mixer adapted to mix the first fluid with the second fluid; and a first fluid sprayer located downstream from the fluid mixer.
 2. The cleaning device of claim 1, wherein the fluid deposition system further comprises a check valve fluidly positioned between the second supply tank and the fluid mixer and adapted to prevent fluid from flowing in a direction from the fluid mixer to the second supply tank.
 3. The cleaning device of claim 1, wherein the cleaning head further comprises a flow valve adapted to block the flow of the first fluid in an off position, and allow the flow of the first fluid in at least one operating position.
 4. The cleaning device of claim 3, wherein the flow valve is fluidly positioned between the fluid hose and the fluid mixer.
 5. The cleaning device of claim 1, wherein the fluid mixer comprises an eductor.
 6. The cleaning device of claim 1, wherein the cleaning head further comprises a diverter valve adapted to create a rinse flow path from the fluid hose to a second fluid sprayer, wherein the rinse flow path bypasses the fluid mixer.
 7. The cleaning device of claim 1, wherein the fluid deposition system further comprises a third supply tank adapted to contain a third fluid, and the fluid mixer is adapted to selectively mix the first fluid with the second fluid in a first mixer position, and with the third fluid in a second mixer position.
 8. The cleaning device of claim 7, wherein the fluid mixer comprises: an eductor; and a selector valve fluidly positioned between the second supply tank, the third supply tank and the eductor, the selector valve being adapted to selectively fluidly connect the eductor to the second supply tank in a first selector valve position, and to the third supply tank in a second selector valve position.
 9. A cleaning device comprising: a housing adapted to hold: a first supply tank adapted to contain a first fluid; a recovery tank; a vacuum fan adapted to generate a working air flow through the recovery tank; and a fluid pump having a pump inlet and a pump outlet, the pump inlet being adapted to receive the first fluid from the first supply tank; a hose assembly having a proximal end connected to the housing and a distal end freely moveable relative to the housing, the hose assembly comprising: a vacuum hose in communication with the recovery tank; and a fluid hose in communication with the pump outlet; a cleaning head connected to the distal end of the hose assembly, the cleaning head comprising: an inlet nozzle in communication with the vacuum hose; and a fluid deposition system in communication with the fluid hose, the fluid deposition system comprising: a second supply tank adapted to contain a second fluid, the second supply tank being selectively removable from the cleaning head; a tank receptacle, adapted to receive substantially the entire second supply tank, and comprising an open portion through which at least a portion of the second supply tank is visible; a fluid mixer adapted to mix the first fluid with the second fluid; and a first fluid sprayer, located downstream from the fluid mixer.
 10. The cleaning device of claim 9, wherein the second supply tank comprises a dry-break valve that automatically seals the second supply tank upon removal of the second supply tank from the cleaning head.
 11. The cleaning device of claim 9, wherein the fluid deposition system further comprises a check valve fluidly positioned between the second supply tank and the fluid mixer and adapted to prevent fluid from flowing in a direction from the fluid mixer to the second supply tank.
 12. The cleaning device of claim 9, wherein the cleaning head further comprises a flow valve adapted to block the flow of the first fluid in an off position, and allow the flow of the first fluid in at least one operating position.
 13. A cleaning device comprising: a housing adapted to hold: a first supply tank adapted to contain a first fluid; a recovery tank; a vacuum fan adapted to generate a working air flow through the recovery tank; and a fluid pump having a pump inlet and a pump outlet, the pump inlet being adapted to receive the first fluid from the first supply tank; a hose assembly having a proximal end connected to the housing and a distal end freely moveable relative to the housing, the hose assembly comprising: a vacuum hose in communication with the recovery tank; a fluid hose in communication with the pump outlet; and a hose cuff located at the distal end; a cleaning head comprising: an inlet nozzle in communication with the vacuum hose; and a fluid deposition system in communication with the fluid hose, the fluid deposition system comprising: a flow valve adapted to block the flow of the first fluid in an off position, and allow the flow of the first fluid in at least one operating position; a second supply tank adapted to contain a second fluid; a fluid mixer adapted to mix the first fluid with the second fluid; a first fluid sprayer, located downstream from the fluid mixer; and wherein the cleaning head is selectively connectable to the hose cuff such that the cleaning head can be simultaneously connected to the vacuum hose and the fluid hose.
 14. The cleaning device of claim 13, wherein: the hose cuff comprises a first vacuum connection sleeve and a first fluid coupler, the first vacuum connection sleeve and the first fluid coupler being fixed relative to one another; and the cleaning head further comprises a second vacuum connection sleeve adapted to slidably engage with the first vacuum connection sleeve and a second fluid connector adapted to slidably engage with the first fluid coupler, the second vacuum connection sleeve and the second fluid coupler being fixed relative to one another.
 15. The cleaning device of claim 13, wherein the cleaning head and the hose cuff are held in connection with one another by a snap fitting.
 16. The cleaning device of claim 13, wherein the second supply tank is selectively removable from the cleaning head and comprises a dry-break valve that automatically seals the second supply tank upon removal of the second supply tank from the cleaning head.
 17. The cleaning device of claim 13, wherein the fluid deposition system further comprises a check valve fluidly positioned between the second supply tank and the fluid mixer and adapted to prevent fluid from flowing in a direction from the fluid mixer to the second supply tank.
 18. The cleaning device of claim 13, wherein the flow valve is fluidly positioned between the fluid hose and the fluid mixer.
 19. The cleaning device of claim 13, wherein the fluid mixer comprises an eductor.
 20. The cleaning device of claim 13, wherein the cleaning head further comprises a diverter valve adapted to create a rinse flow path from the fluid hose to a second fluid sprayer, wherein the rinse flow path bypasses the fluid mixer.
 21. A cleaning device comprising: a housing adapted to hold: a first supply tank adapted to contain a first fluid; a recovery tank; a vacuum fan adapted to generate a working air flow through the recovery tank; and a fluid pump having a pump inlet and a pump outlet, the pump inlet being adapted to receive the first fluid from the first supply tank; a hose assembly having a proximal end connected to the housing and a distal end freely moveable relative to the housing, the hose assembly comprising: a vacuum hose in communication with the recovery tank; and a fluid hose in communication with the pump outlet; a cleaning head connected to the distal end of the hose assembly, the cleaning head comprising: an inlet nozzle in communication with the vacuum hose; a handle; and a fluid deposition system in communication with the fluid hose, the fluid deposition system comprising: a flow valve adapted to block the flow of the first fluid in an off position, and allow the flow of the first fluid in at least one operating position; a second supply tank adapted to contain a second fluid; a fluid mixer adapted to mix the first fluid with the second fluid; a first fluid sprayer, located downstream from the fluid mixer; and a diverter valve adapted to create a rinse flow path from the fluid hose to a second fluid sprayer, wherein the rinse flow path bypasses the fluid mixer; wherein the flow valve and the diverter valve are positioned proximal to the handle such that a user can grip the handle in one hand and operate the flow valve and the diverter valve with the one hand without releasing the handle.
 22. The cleaning device of claim 21, wherein the second supply tank is selectively removable from the cleaning head and comprises a dry-break valve that automatically seals the second supply tank upon removal of the second supply tank from the cleaning head.
 23. The cleaning device of claim 21, wherein the fluid deposition system further comprises a check valve fluidly positioned between the second supply tank and the fluid mixer and adapted to prevent fluid from flowing in a direction from the fluid mixer to the second supply tank.
 24. The cleaning device of claim 21, wherein the flow valve is fluidly positioned between the fluid hose and the fluid mixer.
 25. The cleaning device of claim 21, wherein the fluid mixer comprises an eductor.
 26. A cleaning device comprising: a housing adapted to hold: a first supply tank adapted to contain a first fluid; a recovery tank; a vacuum fan adapted to generate a working air flow through the recovery tank; and a fluid pump having a pump inlet and a pump outlet, the pump inlet being adapted to receive the first fluid from the first supply tank; a hose assembly having a proximal end connected to the housing and a distal end freely moveable relative to the housing, the hose assembly comprising: a vacuum hose in communication with the recovery tank; and a fluid hose in communication with the pump outlet; a cleaning head connected to the distal end of the hose assembly, the cleaning head comprising: an inlet nozzle in communication with the vacuum hose; and a fluid deposition system in communication with the fluid hose, the fluid deposition system comprising: a second supply tank adapted to contain a second fluid; a third supply tank connected to the second supply tank and adapted to contain a third fluid; a fluid mixer adapted to selectively mix the first fluid with the second fluid in a first mixer position, and with the third fluid in a second mixer position; and a first fluid sprayer located downstream from the fluid mixer.
 27. The cleaning device of claim 26, wherein the second supply tank and third supply tank comprise separate chambers of a multi-chambered supply tank.
 28. The cleaning device of claim 26, wherein the second supply tank and the third supply tank are selectively removable from the cleaning head.
 29. The cleaning device of claim 28, wherein the second supply and third supply tank each have a dry-break valve that automatically seals the respective tank upon removal of the second supply tank and third supply tank from the cleaning head.
 30. The cleaning device of claim 26, wherein the fluid mixer comprises: an eductor; and a selector valve fluidly positioned between the second supply tank, the third supply tank and the eductor, the selector valve being adapted to selectively fluidly connect the eductor to the second supply tank in a first selector valve position, and to the third supply tank in a second selector valve position.
 31. The cleaning device of claim 26, wherein the cleaning head further comprises a flow valve adapted to block the flow of the first fluid in an off position, and allow the flow of the first fluid in at least one operating position.
 32. The cleaning device of claim 26, wherein the cleaning head further comprises a diverter valve adapted to create a rinse flow path from the fluid hose to a second fluid sprayer, wherein the rinse flow path bypasses the fluid mixer.
 33. A cleaning device comprising: a first supply tank adapted to contain a first fluid; a recovery tank; a vacuum fan adapted to generate a working air flow through the recovery tank; a fluid pump having a pump inlet and a pump outlet, the pump inlet being adapted to receive the first fluid from the first supply tank; a fluid supply hose fluidly connected to the pump outlet; a bypass valve fluidly positioned between the fluid supply hose and the pump inlet; a fluid deposition system in fluid communication with the fluid supply hose, the fluid deposition system comprising: a flow valve adapted to block the flow of the first fluid in an off position, and allow the flow of the first fluid in at least one operating position; a first fluid sprayer located downstream from the flow valve; and wherein the bypass valve is adapted to open when the flow valve is in the off position.
 34. The cleaning device of claim 33, wherein the bypass valve comprises a spring-biased valve that opens when the pressure in the fluid supply hose reaches a predetermined pressure, the predetermined pressure occurring when the fluid pump is operating and the flow valve is in the off position.
 35. The cleaning device of claim 33, wherein the fluid deposition system further comprises: a second supply tank adapted to contain a second fluid; and a fluid mixer, fluidly located between the first supply tank and the first fluid sprayer, and adapted to mix the first fluid with the second fluid.
 36. The cleaning device of claim 35, wherein the fluid mixer comprises an eductor.
 37. The cleaning device of claim 35, wherein the fluid deposition system further comprises: a third supply tank adapted to contain a third fluid; and wherein the fluid mixer is adapted to selectively mix the first fluid with the second fluid in a first mixer position, and with the third fluid in a second mixer position.
 38. The cleaning device of claim 33, wherein: the first supply tank, recovery tank, vacuum fan, fluid pump, and bypass valve are contained in a housing; the flow valve and the first fluid sprayer are contained in a cleaning head having a vacuum inlet nozzle; and the cleaning head is attached to the housing by a hose assembly comprising: a proximal end connected to the housing; a distal end freely moveable relative to the housing; a vacuum hose in fluid communication between the recovery tank and the vacuum inlet nozzle; and at least a portion of the fluid supply hose.
 39. The cleaning device of claim 38, wherein the fluid deposition system further comprises: a second supply tank adapted to contain a second fluid; and a fluid mixer, fluidly located between the first supply tank and the first fluid sprayer, and adapted to mix the first fluid with the second fluid.
 40. The cleaning device of claim 39, wherein the second supply tank is selectively mountable in the cleaning head and comprises a dry-break valve that automatically seals the second supply tank upon removal of the second supply tank from the cleaning head.
 41. The cleaning device of claim 39, wherein the cleaning head further comprises a diverter valve adapted to create a rinse flow path from the fluid supply hose to a second fluid sprayer, wherein the rinse flow path bypasses the fluid mixer.
 42. The cleaning device of claim 38, wherein: the hose assembly further comprises a hose cuff located at the distal end; and wherein the cleaning head is selectively connectable to the hose cuff such that the cleaning head can be simultaneously connected to the vacuum hose and the fluid supply hose.
 43. A cleaning device comprising: a housing having an air inlet, an air outlet and a motor cooling path therebetween; a first supply tank selectively removable from the housing for containing a first fluid; a fluid deposition system fluidly connected to the first supply tank, and adapted to deposit the first fluid on a surface to be cleaned; a recovery tank selectively removable from the housing; a vacuum fan located within the housing; a fan motor located within the motor cooling path and adapted to drive the vacuum fan to generate a working air flow through the recovery tank; and a motor cooling fan located within the motor cooling path and adapted to generate a cooling air flow, along the motor cooling path, that enters the housing through the air inlet, is heated by the fan motor, and exits the housing through the air outlet; and wherein the first supply tank is located adjacent at least a portion of the motor cooling path between the fan motor and the air outlet, and the first fluid is adapted to be heated by the cooling air flow.
 44. The cleaning device of claim 43, wherein the housing comprises an upright housing having a base portion and a handle portion pivotally attached to the base portion.
 45. The cleaning device of claim 43, wherein the fan motor is positioned below the first supply tank.
 46. The cleaning device of claim 43, wherein the first fluid supply tank is located in a pocket in the housing, and the motor cooling path is adjacent to at least a portion of the pocket.
 47. The cleaning device of claim 43, wherein the housing and/or the supply tank further comprises one or more heat transfer enhancing surfaces.
 48. The cleaning device of claim 47, wherein the housing comprises a first heat transfer enhancing surface, the supply tank comprises a second heat transfer enhancing surface, and the first and second heat transfer enhancing surfaces abut one another when the supply tank is installed in the housing.
 49. The cleaning device of claim 43, wherein the motor cooling path is contained within a generally isolated conduit within the housing.
 50. The cleaning device of claim 43, wherein at least a portion of the motor cooling path is contained within a generally isolated conduit within the housing.
 51. The cleaning device of claim 43, further comprising a temperature sensor adapted to display the thermal condition of the first fluid.
 52. The cleaning device of claim 43, further comprising: a hose assembly comprising a vacuum hose in fluid communication with the recovery tank and a fluid supply hose in fluid communication with the fluid deposition system, the hose assembly having a proximal end connected to the housing, and a distal end freely moveable relative to the housing; and a cleaning head attached to the distal end of the hose assembly, the cleaning head comprising: an inlet nozzle in communication with the vacuum hose; and a fluid sprayer in fluid communication with the fluid supply hose.
 53. The cleaning device of claim 52, wherein the cleaning head further comprises: a second supply tank adapted to contain a second fluid; and a fluid mixer adapted to mix the first fluid with the second fluid.
 54. A cleaning device comprising: a housing; a supply tank that is selectively removable from the housing and is adapted to contain a fluid; a recovery tank; a vacuum fan adapted to generate a working air flow through the recovery tank; and a temperature sensor comprising: a first element attached to the supply tank; a second element attached to the housing; and a display positioned to indicate the thermal condition of the fluid to an operator.
 55. The cleaning device of claim 54, wherein: the first element comprises a thermally-conductive element adapted to extend into the supply tank to contact the fluid; and the second element comprises a temperature sensing element adapted to contact the first element when the supply tank is attached to the housing.
 56. The cleaning device of claim 54, wherein the display indicates the temperature of the fluid in numerical degrees.
 57. The cleaning device of claim 54, wherein the display comprises a light that is illuminated or extinguished when the fluid reaches a predetermined temperature.
 58. A cleaning device comprising: a housing; a supply tank that is selectively removable from the housing and is adapted to contain a fluid; a recovery tank; a vacuum fan adapted to generate a working air flow through the recovery tank; and a temperature sensor attached to the supply tank and adapted to indicate the thermal condition of the fluid to an operator.
 59. The cleaning device of claim 58, wherein the temperature sensor comprises a thermochromic material.
 60. A cleaning device comprising: a fluid supply system comprising: a first supply tank for containing a fluid; and a fluid deposition system, associated with the first supply tank and adapted to deposit the fluid on a surface to be cleaned; a fluid recovery system comprising: a recovery tank; an inlet nozzle; and a vacuum fan adapted to generate a working air flow from the inlet nozzle to the recovery tank; one or more ultraviolet lights adapted to irradiate the fluid supply system and/or the fluid recovery system.
 61. The cleaning device of claim 60, wherein the fluid deposition system comprises: a fluid pump having an inlet and an outlet, the inlet being adapted to receive the fluid from the first supply tank; and a fluid sprayer in fluid communication with the pump outlet and adapted to spray the fluid on the surface being cleaned.
 62. The cleaning device of claim 61, wherein the cleaning device further comprises: a hose assembly comprising a vacuum hose in fluid communication with the recovery tank and a fluid supply hose in fluid communication with the fluid deposition system, the hose assembly having a proximal end connected to the housing, and a distal end freely moveable relative to the housing; and a cleaning head attached to the distal end of the hose assembly, the fluid sprayer and inlet nozzle being located on the cleaning head.
 63. The cleaning device of claim 62, wherein the cleaning head further comprises: a second supply tank adapted to contain a second fluid; and a fluid mixer adapted to mix the first fluid with the second fluid. 